'Not necessary - we searched them ourselves when we saw that someone had fired the hut . . .'

Conway intervened, made a magnificent job of his intervention as his voice shook with genuine fury. 'This is an outrage! You come here and suggest searching the place? This is United States territory, Mr Vassily.' He stood away from the table as he faced Papanin. 'I hope I don't have to remind you that the American flag flies over this ice island?'

Papanin paused, stooped over, half inside his parka as he looked at Conway. He was going to shake these people before he left. 'I saw the flag when we came in - hanging limp like a piece of frozen cod.' He stood upright, fastening his coat. 'It might be safer if none of you leave this ice island until your plane arrives.'

'Safer from what?' Beaumont asked.

'If we see something moving on the pack my men may assume it is Marov and shoot,' Papanin said grimly. 'I have told them he must be taken unharmed - if possible. But Gorov had many friends and some of them are outside this hut - and all of them are armed.' He pulled the fur hood over his shaven head. 'Kramer, we did ask for these people's cooperation. Since we are no longer welcome we will go.' He glanced round the hut. 'A pleasant trip back to the United States, gentlemen. Here you are living on borrowed time.'

When they had gone Beaumont sent Grayson out to make sure they had really gone, then he looked at Conway who was drying his moist palms with a handkerchief. 'It's going to be extremely tricky from now on,' he warned. 'The man who called himself Vassily is Col Igor Papanin, head of Special Security in Leningrad - I was shown his photograph before I left Washington.' Beaumont checked his watch. 1.45 am. 'I'm going to take Gorov out by sled at eight o'clock this morning - in six hours' time. That will give us the best chance of avoiding the Russians.'

'Why eight o'clock?'

'Because by then they'll have been up all night somewhere out on the pack - waiting to see what happens. They'll have had six hours of it - listening hard, shivering, straining to see any sign of movement. By eight o'clock they'll be bad-tempered, bone-tired and not very alert. But it would help if I had a diversion when we move off.'

'I'll drive the Sno-Cat around,' Conway suggested quickly. 'I can take it across the island, down the ramp and move round on the pack a bit.'

'Which was what I was going to suggest - up to a point anyway.' Beaumont stood up, his eyes heavy, his limbs sluggish. He started walking around to keep himself awake. 'They found their way here in Sno-Cats - God knows how -and they may be carrying some kind of mobile radar. If you take the Sno-Cat out they'll concentrate on it - while we slip off the western end of the island.'

'It should fox them ...'

'Listen, Matt.' Beaumont spoke with deliberation to stress the risk Conway would be running. 'There's a bunch of armed Russians within a mile of this hut, so you're not to take any unnecessary chances. I think I knocked Papanin off his perch when I said a signal had been sent...'

'He'll find out when he checks with his monitoring unit.'

For a moment Beaumont wondered whether to tell Con-way about his own transmitter, then he decided against it. It was an even chance that Papanin would be back again, and next time he might ask questions rather more forcefully. 'That won't be until he gets back to North Pole 17,' he said. 'You can drive your Sno-Cat safely round the eastern part of the island - in this fog?'

'I've lived on this island for three years - in all weathers,' Conway assured him. 'I can put on the airstrip landing lights to guide me, I've got an angled beam on the Cat which shows me the way down the ramp . . .'

'Not down the ramp!' Beaumont said sharply. 'The island has your flag flying over it - once you go down on to the pack it's no-man's land. If you're going to help at all you just drive around slowly on the island for an hour or so. On the island,' he repeated.

They had a great deal to do during the next half hour. They called Langer out of the hut where he had stayed with the dogs to keep them quiet during Papanin's visit. They released Rickard from the hut next door where he had been locked in with the unconscious Sondeborg - ostensibly to keep an eye on the unstable gravity specialist, but also to prevent his hearing about the presence of Gorov on the island. Beaumont was determined that Conway would be the only man left behind on Target-5 who would know about Michael Gorov.

They left Conway and Rickard in the headquarters hut, and then Beaumont took the others with him to 'get Gorov out of the refrigerator', as he put it. Mercifully the Russian oceanographer was still asleep, still under the influence of the sedative when they lifted the trap-door in the research hut and hauled up his cocooned body. Had he woken up inside the deep tomb alone his reaction was something the imagination preferred not to dwell on - until he discovered the scribbled note Beaumont had left beside the lamp they had lowered with the heater.

Wrapped in many blankets, Gorov was surprisingly warm when they lifted him into the single bunk Conway had installed inside the research hut. He woke up as Conway slipped inside and closed the door. 'I wanted to see if he was OK,' the American explained. 'It gave me the horrors to think of him lying down there.'

'This place is different,' Gorov said as he eased himself up on one elbow. 'You have moved me to a new hut. Why?'

Surprisingly alert, Beaumont noted, but a man who had made his way alone across the pack from North Pole 17 had to be unusually tough. He asked Conway to examine him again and lit a cigarette while he waited impatiently for the verdict. He was convinced they only had a few hours to get away from the ice island. Papanin would soon recover from the shock of his initial reception and then he would be back - and the second visitation would be much more dangerous than the first.

'He seems in good condition,5 Conway said as he stood up from his patient. 'I can't understand it - after that ordeal.'

Beaumont started his interrogation at once, firing questions at the Russian who spoke good English. Like Papanin, Gorov had learned his English at the Kharkov language laboratory, a knowledge essential to his work. Once French had been the international language of the scientific fraternity, but for a quarter of a century it had been replaced by English - and Gorov liked to read scientific works in the original language. He was obviously taken aback by Beaumont's verbal onslaught.

'When were you last in Kiev?'

'Last week.'

'Meet any relatives there?'

'My brother, Peter . . .'

'He's in the Navy?'

'No, he's on a trawler . . .'

'What was the name of your girlfriend who died?'

Gorov's thick lips tightened. He stared bleakly at Beaumont. 'She was my fiancee. We were going to be married

'I asked for her name.'

'Rachel Levitzer. Is all this really necessary?'

'Yes! Is it by God?' Conway burst out, appalled by Beaumont's brutality.

'Yes, it is by God,' Beaumont replied tersely. He watched Gorov very carefully. 'Col Igor Papanin was standing in this very room half an hour ago.'

Fear flashed into the Russian's eyes. He stared round the hut like a trapped man, tried to say something, swallowed uncomfortably. It was the instantaneous reaction Beaumont had been hoping for; if this man had been a stooge - sent to the island by Papanin as a spy - he couldn't have pretended naked fear so spontaneously.

Beaumont explained what he had been doing and the reasons for it. No photograph was available in Washington of Michael Gorov and this was the only way to check his identity. At least now when they started out across the ice on their terrible journey they would know they were taking the right man.

Conway gave Gorov a drink from the bottle of brandy he had brought with him, a bottle he kept securely locked away in a cupboard so that Sondeborg wouldn't guzzle the lot. At Beaumont's suggestion he prepared food for the Russian on a primus in the research hut, and all the time the fugitive sat at the edge of the bunk, lacing and unlacing his strong fingers, running them nervously through his lank black hair.

Earlier, soon after the interrogation had ended, he had got up to stretch his legs and had wandered over to the chair where his parka lay draped. Casually, he had lifted the parka to sit for a moment; even more casually he had run his hand over the pocket which contained the core tube, had felt its cylindrical shape under the fur. Langer, standing near the door, smiled to himself as Gorov sat down, visibly relaxed that his precious possession was still safe.

That night it was fatal for Beaumont to think of sleep. He had just said that he was going back to the headquarters hut to lie down for a while when they all heard it. The distant drone of an aircraft coming in. The Hercules 0130 transport which Dawes, worried stiff by the 'sabotage' signal, had sent, was circling overhead, waiting to land.

Col Igor Papanin was also listening to the drone of the American transport plane. A few hundred metres away from the snow ramp leading down from Target-5 he sat in the cab of his Sno-Cat alongside Kramer, calmly puffing at his little curved pipe. The atmosphere inside the sealed cab was thick with smoke, so thick that Kramer thought he would soon expire. But he dare not open a window because that would let the Arctic flood in.

'They've switched the landing lights on,' he said nervously. The blurred glow of a single landing light wobbled beyond the top of the cliffs, then the fog masked it.

'Naturally,' Papanin said, 'they have to show their plane where to land.'

'And you still think Gorov isn't there?'

'I said I wasn't convinced that he had yet arrived - a different thing, Kramer. I was looking for fear and anxiety when we arrived but all I detected was indignation. That big man was very aggressively indignant.' he said thoughtfully.

'But if he has arrived - and the plane lands?' 'You worry too much. It's going to be all right - you'll see.'

Seven hundred feet above Target-5 the plane's pilot, Alfred Ridgeway, sat in front of his controls as he circled over what another pilot, Arnold Schumacher, had called the oatmeal, the thick bank of dirt-grey fog below him. In the cargo compartment behind him two rows of bucket seats lined the fuselage and the rear seats were occupied by twelve men in Arctic clothing who carried concealed weapons.

The twelve men belonged to the US Coastguard Service and they had been specially chosen for this job. In Leningrad the Russians had sent a Special Security detachment to the Arctic because this gave the expedition a non-military character - which neutralized the danger of an international incident building up only a few months before the Summit meeting in Moscow. Washington was taking the same precaution for the same reason: there must be no danger of an international incident.

The two seats nearest the pilot's cabin were occupied by a different type of passenger, by a doctor and a nurse. Dr Maxwell Hergsheimer, forty-eight years old and grey-haired, who was equipped with a medical kit and oxygen cylinders for his Russian patient, stared out of the window as the fog rolled in great banks below. Behind him sat Nurse Anne Clyde from Brooklyn, the thirty-year-old girl who had volunteered to come with him. Hergsheimer was worried about her; not every girl would have so calmly contemplated a trip out over the polar wastes. And to emphasize the civilian character of their mission she wore her uniform. She leaned forward over his shoulder. 'Do you think Captain Ridgeway will get us down?' she inquired.

'I think so, yes. He comes from my home state, Illinois, and I've known him for years. He'll go on circling until he does see his way in.'

In the pilot's cabin Ridgeway's sentiments were rather less optimistic. In fact, Ridgeway was very worried indeed. There was no sign of a gap in the fog anywhere; if anything it was getting worse as it floated like a dark, poison-gas cloud under the pallid light of the moon. He glanced at the fuel gauge. Plenty left: he'd damned well go on circling until there was only enough gas to get them back to Curtis.

'I'm beginning to wonder whether I saw those landing lights at all,' van Beeck, his co-pilot, commented.

'Want to go home, Jim? You said you saw them - did you?'

'I saw them, Captain.'

'OK. So we keep circling.'

Beaumont was sweating with anxiety as he stood close to one of the landing lights Conway had switched on. In the fog it glowed like a small greenish fire. He was standing with Conway at the edge of the airstrip, a quarter of a mile away from the cluster of huts where five more men waited in equal anxiety. Then he heard the faint drone of the plane coming back, a drone growing steadily louder.

'Thank God,' Conway muttered. 'I thought he'd given up.'

Thank God, Beaumont agreed to himself. And the fog was thinning a little. The plane only had to land to secure their salvation; at Curtis Field Dawes had told him about the coastguard detachment standing by and Beaumont was confident it would be on board. With a detachment of a dozen armed men on the island Papanin would be checkmated.

'Do you think he can land in this stuff?' Conway whispered.

In the fog, whispering came naturally. It shifted all around them, assuming strange, menacing shapes, and the cold was intense. They shifted their boots frequently, stretched their toes inside them, anything to keep a fraction of circulation moving while they waited and the invisible plane's engines built up into a muffled roar. Soon it was dead overhead, and the fog thinned a little more. But not enough, Beaumont was thinking. 'He can't be thinking of landing yet,' he murmured. 'I wonder what visibility is like up there .. .'

Visibility from five hundred feet up had improved: instead of being impossible it was bad to awful. Ridgeway banked the plane more steeply to get a better look down and grunted. It was a habit of which he was unaware - grunting - but the noise was significant for van Beeck. It told the copilot that his captain had just taken a tricky decision. He waited while Ridgeway stared hard into the fog.

The pilot had seen the landing lights, he had guessed that this improved situation would be short-lived, that soon the fog would roll over again. It would have been a considerable overstatement to say that the parallel lines of lights were visible - they showed to Ridgeway in the banked plane as two vague strings of pale glows: no more, but they showed him where the airstrip was. It was between those two faint lines and that was enough for him.

'We're going in,' he said. 'Tell them.'

The co-pilot left his seat, went back into the cargo compartment and called out to his fourteen passengers. 'Time to strap yourselves in - we're going down . . .'

'You see,' Dr Hergsheimer told Nurse Clyde, 'I was right - he's from Illinois.'

In the control cabin Ridgeway was banking his machine away from the island, turning in a wide sweep to give himself a good run-in. The lights had vanished now and he was praying he would see them again when he had completed his turn. The sweep continued, swinging out over the desolate polar pack which was invisible, then he was on course, screwing up his eyes as he stared ahead.

The damned lights seemed fainter now, hardly more than a blurred phosphorescence beneath the fog. The machine went into a shallow glide, the blur came up to meet it. Gear and flaps down. The four propellers whipped through wisps of fog, the motors beat steadily, the ice island came up to meet them. It was an exercise Ridgeway had repeated many times before. He had landed five times on Target-5 in various parts of the Arctic - all of them hundreds of miles north of this latitude.

Don't overshoot! The warning flashed through his brain. There was just sufficient length of airstrip to land on - provided he touched down in time. The lights merged into glow-lines, the skids touched down, the machine wobbled as though starting to skid, so they were tearing over the ice blind except for the glow rushing past them on either side. So long as there was no obstruction in the way. . . The propellers beating the air thrashed up a storm of snow, obliterating the glow on either side, and then Ridgeway completed the landing, reversing propeller pitch and braking to bring the machine to a halt.

Beaumont and Conway were at the edge of the airstrip when they heard the increase in engine sound and realized the transport was coming in to land. 'Get well back!' Beaumont shouted. They moved away from the airstrip, went back a short distance, and when they turned round the lights of the plane were visible, dropping towards them at what seemed slow-motion speed.

'God! He's going to overshoot . ..' Conway stood quite still, frozen with fear as well as with cold.

'He'll make it!' Beaumont shouted the words above the roar of the engines. The fog made distance impossible to judge, visibility from above must be better than it seemed at ground level - otherwise the pilot would never have attempted the landing. Beaumont saw the wings which carried the lights, a dark silhouette plunging through fog swirls as it thundered along the airstrip. In the Arctic night the engines were deafening, a thudding roar, then the machine touched down, sent up spurts of snow as the skis sped along the ice, sent up cloudbursts of snow as the propellers churned. The plane seemed enormous bursting through the fog. Then it was past them and Beaumont thought he heard the hiss of skis above the roar. Their aerial taxi had arrived. The plane went on through the fog. They heard the engine sound change as the pilot reversed propeller pitch. In a moment the machine would be stationary, its propellers ticking over as the pilot cut his motors. They could still see it as a blurred, retreating shape when the silhouette altered. One moment it was horizontal, the next moment it was swinging up vertically, the tail high in the air, then the tail smashed down, vanished. The vibration of the impact travelled through the ice, echoed up their legs. The petrol tanks detonated, deafened Beaumont. The flare of flame, the flash which seared right through the fog, blinded him for a moment. Then there was crackling fire, black smoke.

As the echo of the detonation died away Papanin opened the window and knocked out his pipe. 'You see, Kramer, I said it would be all right.'

There were no survivors. The heat was so intense that for a brief time it burned a hole in the fog, exposing moonlit sky before the smoke masked it again. The plane was burning itself to cinders on a carpet of ice and the inferno faded suddenly, leaving only creeping smoke and a nauseous stench which turned Beaumont's stomach, a stench compounded of petrol, plane - and people.

He had completed a careful circuit of the disaster when Conway, breathing heavily, caught up with him. 'There must be someone alive . . .'

'It's hopeless, Conway. No one could survive that - you might just as well have shoved them head first into an incinerator.'

'Beaumont - look at this . . .' The American's voice trembled and he was holding something in his hand, something crumpled and smeared with oil. He opened it put, reassembled it into a caricature of its original shape. 'Beaumont, it's a nurse's cap.'

'They must have brought her to attend to Gorov ...'

'Why the hell had that plane to crash? It was down - it was safe, it was stopping when ...'

'Come over here.' Beaumont walked a few paces on to the airstrip, bent down and heaved at a large object close to a skid-mark which scarred the snow. 'This is why, Conway. The plane caught this rock arid somersaulted. One of the machine's skids is over there - it must have ripped away when it struck the boulder.'

'I swept the airstrip with the snow-plough - swept it two days ago.' Conway sounded bewildered, in a state of shock. 'I just couldn't have missed a thing that size ...'

'You missed this One, too.' Beaumont moved a few feet further across the airstrip and hammered his boot against a second snow-covered boulder. 'And that one . . .' He had only just seen the third obstruction and he bent down to examine it, telling the American to focus his lamp on it. Conway stared down at the rock in silence as Beaumont heaved it over and scraped at the underside with his gloved fingers.

'You missed all three of them,' Beaumont continued, 'for the very simple reason they weren't here when you swept the airstrip. There's very little snow underneath this rock and not much more on top - what, there is came from the whirling propellers.'

'You mean ...'

'Yes! These boulders are from the hill behind the camp -and boulders don't walk a quarter of a mile. They were carried here in case a plane did try to land. It's sabotage again, Conway - sabotage of the most brutal kind. God knows how many poor devils were on that plane besides the nurse.'

The bastards!'

'Take it easy. We've got to get back to the camp.'

'I'll see this gets into every newspaper in America ...'

'You won't, you know.' Beaumont took a grip on Conway's arm. and started him moving. 'You haven't got a shred of evidence to back up that statement...'

'The boulders, for God's sake!'

'The Russians would say the rocks must have been there all the time, that the wind blew snow away and exposed them - maybe even that it was your fault for not sweeping the strip properly. Someone has organized a very nasty and very effective accident. I just hope it's not setting a pattern for the future.'

The Sno-Cat ground its way through the fog, the two pairs of heavy tracks kicking up the devil of a row as they revolved over the ice. One headlight beam poked at the fog beyond the cab, the second light mounted outside the cab window was angled downwards. Inside the cab Conway leaned well over to check the angled light: he was going to depend on that lamp soon, depend on it to stop him plunging twenty feet over a sheer drop down on to the polar pack,

Muffled inside his fur parka and fur hood, he checked his watch. 5am exactly. So he had got the timing right; in a few minutes he should see one of the airstrip landing lights he had switched on. He moved the gear lever, moved the big lever which turned the tracks, checked the milometer as he changed direction. Conway, a peaceable man, had a loaded rifle on the seat beside him as he drove on into nothing with the memory of the nurse's cap vivid in his mind. Screwing up his eyes, he frowned: the windscreen was messed up and the wipers were spreading dirt over the glass. He stopped the Cat, left the engine ticking over and climbed out with a cleaning rag.

Fog rolled over the Sno-Cat, blotted out the rear of the vehicle, and Conway looked round nervously as he rubbed at the glass. Fog everywhere, fog which could conceal an army of Russians. He cleaned the glass quickly, got back up into the cab, and the closing of the door was a relief, made him feel a little safer because he was high up and enclosed.

He checked the milometer, moved the big lever and the cumbersome machine ground slowly forward. The dangerous part was coming.

Crouched over his levers, the American leaned close to the windscreen where the wipers kept a fan-shaped segment clear of moisture. He must be close to the cliff now - if he had any idea of where he was going - and now he was staring at the ground below the angled headlight. Entirely on his own, Conway was extending Beaumont's deception plan - he was going to drive the Sno-Cat to the ramp, take it down on to the pack and drive it a quarter of the way round the island. With the aid of the angled headlight he could keep the cliff in view and avoid any risk of losing himself out on the pack.

Then he was going to abandon the Sno-Cat, walk back to the ramp and return to camp. He would leave the Sno-Cat with its nose pointed north, its steering mechanism jammed. When the Russians found it they would assume that someone had escaped from the island - panicked by the plane crash -and that they were heading north instead of west.

With one hand he lit a cigarette, and that made him feel a little better. Then he changed course suddenly. The angled light had projected its beam into a vacuum, into nothing. He was moving along the edge of the cliff-top. For safety's sake he took the vehicle back a dozen yards, then he watched for the lamp on top of the wooden post which would tell him he had made it. In a few minutes he would be going down the ramp.

'East... east... east. The ramp.'

Kramer switched off the microphone which linked him with the men on the pack surrounding the island, the men equipped with the Soviet version of the American walkie-talkie transmitter. They would all now be converging, hurrying towards the Sno-Cat - and the ramp.

The Bait was sitting next to Papanin inside the Sno-Cat which was stationary in the fog. In the compartment behind them the radar operator gazed at his scanner, tracking the slow approach of Conway's vehicle across the island. Above him on the roof the radar wing revolved, turning through the fog. It was very quiet out on the pack as Papanin clenched his pipe and stared towards Target-5-

'Do you think Gorov will go with them?' Kramer asked.

'How the hell do I know? There are two possibilities - he is with them, or he isn't. If he is, the problem will be solved. If he isn't, we can go and take possession of an empty camp and wait for him. Can't you work out anything for yourself?'

The Siberian looked through the window to his left. When the fog drifted he could just see the outline of a second Sno-Cat, also stationary and with its engine silent. It carried eight more men, four of them armed with automatic weapons. He looked at his watch. 8.5 am. By 8.15 another piece would have been removed from the board.

Conway was on top of the ramp. He manoeuvred the Cat with great care as he felt the front tracks dropping. Three years ago they had built up the ramp with supporting rocks taken from the hill, they had curved it to follow the cliff wall with a drop to the right so he had to turn the vehicle to the left slowly, keeping very close to the cliff wall.

He braked, kept the engine running, peered out of the window. The angled light shone on no firm surface: it dropped into the fog, gave you the feeling you were looking down a mountainside. Conway's hands were sticky inside his gloves as he went on peering down. Normally he would never have attempted the descent in conditions like these -he was wondering whether to reverse, to go back on to the island.

'To hell with that!'

He spoke the words aloud, a habit he had developed because he was so often alone, carrying out experiments on the pack. The fog obscured everything on the dangerous side; on the other side the light showed a blur of cliff wall. He'd have to concentrate on keeping close to the blur, resisting the temptation to look towards the drop.

Releasing the brake, he started the vehicle turning down the curve, a tricky operation because the huge rear tracks had to haul themselves round after the front caterpillars. He stared at the blurred wall barely a foot away and his seat tilted him forward as the Sno-Cat slanted downwards, its right-hand tracks less than a foot from the brink where the fog hid the pack below. The tracks crawled down the ramp, Conway's hand gripped the lever tightly, sweat dripped off his forehead. Thank God the Cat was responding, was going down nicely. Without warning the vehicle keeled and Conway felt it turning, dropping.

The outer edge of the ramp where supporting rocks had been levered out of the ice collapsed. The huge weight of the vehicle completed the disaster. While Conway was still fighting with the controls the Sno-Cat went over sideways, then went straight down twenty feet on to the hard pack. Conway had switched off the engine, an instinctive reflex when he was going over, and then he was upside down. The roof struck the ice and the terrible weight of the tracks came down on the up-ended floor of the cab, concertinaing the tiny compartment, crushing the man inside into an unrecognizable shape of smashed bone, tissue, metal and glass.

A mile away on the far side of the island, unaware of the tragedy, Beaumont led his small party down on to the pack the Russian security guards had just left and headed westward.

Tuesday, 22 February: 10AM-Noon

This was how the whole world - Europe, the Americas, Australasia, Asia, Africa - might look one day; a lifeless, sterile, frozen desert when the earth moved away from the sun and became an extinct satellite. It was like a preview of the death of the human race.

Wafted by the merest of breezes, a chilling stream of ice-cold air which came direct from the North Pole, the fog had shifted south, exposing the moonlit frozen desert Beaumont and the two sled teams were moving over. They had an endless view to the west and the north, the same God-awful expanse of ice, ice and more ice. Even in the land deserts of the world something grows somewhere; there are isolated oases, pockets of green trees and burning blue water. Here there was nothing but hideous ice - going on for ever.

Pressure ridges loomed in the moonlight ahead of them, a chaos of static ridges ten to twenty feet high. Guided by Grayson's erratic compass they were heading due west, sledding towards distant Greenland over a hundred miles away, and Beaumont was still wondering whether to take out his insurance policy - to head due south instead of west, south to the most dangerous place on earth, Iceberg Alley.

Since the fog had withdrawn its concealing curtain over an hour ago they had seen no sign of the Russians. It was possible that Papanin's men were still patrolling the fringes of Target-5, waiting for Gorov to come in. Beaumont glanced over his shoulder as he drove his sled and Grayson hurried up to him. 'How is our first-class passenger getting on, Sam?'

'Gorov is a pain in the ass,' Grayson said inelegantly. 'He's still sulking over that cross-examination you put him through, and he sits on Horst's sled as though he's some kind of emperor. I'd make the bastard hoof it.'

'Later. He'd just hold us back at the moment. . .' Beaumont broke off, looked quickly into the sky. A small dark blip was coming in from the north-east, heading directly towards them. Like an ugly bird it cruised across the night sky, too far off yet for the blur of its rotor disc to be seen, for the sound of its engine to be heard.

'Chopper! Get under cover . . .'

Beaumont cracked his whip as he shouted the warning, driving the dogs faster towards the shelter of the pressure ridges while behind him Langer shouted at Gorov to get off the bloody sled, to run. The Russian tumbled off the moving sled, fell over on the ice, swore in his own language and then stumbled after them in desperate haste. The sound of the engine beat of the oncoming machine could be heard now, a faint sound growing louder by the second. Beaumont's team plunged through a gap in the first ice wall and then they were inside a corridor, halting as Beaumont pulled at the sled. Langer followed them through the gap as Gorov tried to catch up, still out in the open as the Soviet machine drummed closer. With a curse Grayson grabbed at the Russian and threw him under the lee of the ice wall. They waited, staring up while the dogs, huddled together, also gazed at the sky.

The machine they could no longer see was flying low, no more than two hundred feet above the ice, and if it passed over them they were bound to be spotted. Crouched against the pressure wall which climbed fifteen feet above them, its crest curling over them like a breaking wave, they listened and watched for the helicopter to appear overhead. The throb echo grew louder, vibrated down the ravine where they pressed themselves against the ice. And then Langer was in trouble with the dogs as two of them started to jump about, hating the helicopter's noise, equating it with the machine which had brought them to the edge of the fog bank. He slapped one hard and the animal turned on him, showed its teeth, let out a menacing growl. If the dogs careered out into the ravine it was certain they would be seen. Nothing shows from the air like movement.

Beaumont glanced over his shoulder anxiously, unable to leave his own team which was becoming infected by the commotion. He was astounded to see Gorov crawling along the ground on his knees, stretching out a hand and squeezing the rebellious animal's neck as he called to it in Russian. The animal relaxed, permitted itself to be stroked, and the second dog stopped struggling, staring as though it resented the special treatment its colleague was enjoying. Then something flashed over the ravine, the shadow of the machine.

Before there had been tension, anticipation, now they froze with fear, holding their breath without realizing it. And the dogs froze, too, remained absolutely still. They didn't see the helicopter - only its shadow - then it was flying westward, away from them. 'Stay here till I get back,' Beaumont ordered. Shielded by the pressure wall, he stood up and walked along it until he found a high point on its crest. He clambered up the wall carefully, jabbing his boots into crevices until he could peer over the crest.

It was a good look-out point. Beyond him more jagged ridges spread away, lower ridges he could see over, and about half a mile away the ridges ended and the ice flattened out. The belt of flat ice stretched into the distance like a sheet of plate glass, ideal terrain for them to sled across except for one thing - the Russians were in the way.

Small groups - he counted a dozen - were spaced out over the belt with long distances between them. And they were all sled-teams, moving slowly away from him, heading west towards faraway Greenland. Several miles across the ice two helicopters flew above the pack as though patrolling. The machine which had passed near them landed while he was watching, came down on the level ice close to one of the sled-teams. The rotors had hardly stopped whirling when the door opened and a stream of dogs poured out on to the ice. Men followed the animals, sleds were unloaded, and within minutes the men were harnessing the dogs. The speed of the operation impressed Beaumont. Ten minutes after he had first looked over the crest the helicopter took off, climbed to about five hundred feet and flew off to the northeast. Beaumont slithered back into the ravine, hurried back to where the others were waiting. The argument flared up almost at once.

'Well, it missed us, thank Christ,' Grayson said.

'It wasn't looking too hard - it's just unloaded more sled-teams.'

'More?'

'Sam, not more than half a mile away to the west the ice is lousy with Russian search teams. Some of them are a long way west - and they've got choppers above them.'

'They're coming this way?'

'At the moment they're heading away from us . . .'

'OK. So we creep along behind them.'

'It won't work. Remember that wide belt of smooth ice we saw when we flew in over the pack? They're spread out across that. If we try to cross that belt they'll spot us., Papanin just slammed the door in our faces.'

Short of sleep, the memory of the air crash horror still fresh in his mind, Grayson faced Beaumont and his temper was going fast. 'You're dead wrong, Keith,' he said quietly. 'The only safe way out is westward. We have to hit the Greenland coast. Once we get there we're OK - the Russians can't invade Greenland.'

'A perfect plan,' Beaumont said sardonically, 'except the bit about hitting the Greenland coast. I keep telling you - the Russians are in the way . . .'

'We can slip through those search teams. The ice is big - too big for them to cover it all.'

'You're not getting the message. It's not only the men on the ice - they're patrolling that belt from the air . . .'

'So which way do we go?' Grayson flared. 'North towards the bloody Pole? East back to Target-5 where Papanin's waiting for us? South ...'

'South,' Beaumont interjected. 'That's where we're going.'

Gorov, who had been listening intently, added his own contribution to the growing tension. 'South? That is madness . . .'

'You're not invited into this debate,' Grayson told him roughly. He turned back to Beaumont. 'We'd be heading straight for the edge of the icefield, straight for Iceberg Alley. I suppose when we get there we make the sleds seaworthy and float 'em ail the way down to Cape Farewell?'

'Stop busting a gut,' Beaumont rapped back. 'We'll be going aboard the icebreaker Elroy. She's already coming hell for leather up Iceberg Alley - I fixed that with Dawes in Washington in case something like this happened.'

Grayson was astounded. 'And you really think we have a snowflake's chance in hell of rendezvousing with her?'

'We will rendezvous with her. She's coming up the tenth meridian and we go down it to meet her. You'll have to take frequent star-fixes to check our position.' The decision taken, Beaumont started forming up his own dog team, but Grayson hadn't finished yet.

'You make it sound like we'll be going down the New Jersey Turnpike. The star-fixes may not be accurate - you know that. It would be one pinpoint trying to find another pinpoint . . .'

'With the aid of a little science.' Beaumont pointed to his sled. 'Don't forget we have the Elliott homing beacon. When we get within range of where the Elroy should be we'll send them a signal on the Redifon set. They'll send up the helicopter they have on board and it will home in on our beacon.'

'I don't like it.' Grayson looked at Langer who had listened to the argument in silence. 'Do you like it?'

'Look, Sam . . .' Beaumont's voice hardened. 'That's the way it's going to be. We did the same thing once before when we made rendezvous with the Edisto near Spitsbergen.'

Grayson exploded. 'We were heading for land then! This time we'll be heading for the edge of the icefield - beyond that there's nothing but Iceberg Alley, the ocean .. .'

'Sam,' Langer intervened, 'before Keith started talking what was the last thing you'd have expected him to do?'

'Head south . . .'

'So that's the last thing Papanin will expect us to do.'

Gorov, who had been clasping and unclasping his gloved hands, burst out suddenly. 'I do not think we should do this very crazy thing.'

Grayson turned round and spoke very deliberately to the Russian. 'If it wasn't for you, we wouldn't be in this mess. If you don't like it, you'd better start hiking your way back to Leningrad - because we're going south!'

He formed up his dogs and they moved off with Beaumont in the lead. Within five minutes they were turning through an angle of ninety degrees, heading south away from the great belt of ice where the going would have been so much easier. For over two hours they travelled across ice littered with ravines and pressure walls they had to thread their way through, then Beaumont called a brief halt. It was Grayson who sent the signal on the prearranged wavelength, the signal Dawes was waiting for at Curtis Field.

'Oxygen . .. Strongbow ... Oxygen . . . Strongbow . . .'

He repeated the signal for five minutes before Curtis acknowledged, which was too long because it might be long enough for the Soviet monitors at North Pole 17 to take a radio-direction fix. But the signal had to get through. 'Strongbow' informed Dawes that Michael Gorov had been picked up; 'Oxygen' told him that Beaumont was heading south. Grayson telescoped the Redifon aerial back inside the set and looked up at the sky.

'No Russian planes for two hours,' he said. 'And no American planes either,' he added. 'Those pilots at Curtis must have gone home for the winter. I hope to God the ice-breaker Elroy hasn't gone home too . . .'

* * *

'. . urgent you penetrate icefield for possible rendezvous. Maximum risk must be accepted. Repeat. Must be accepted.'

Commander Alfred Schmidt, USN, captain of the 6,515-ton icebreaker Elroy, still didn't like the signal he had received from Washington three days earlier, and the more he thought about it the less he liked the last part of the signal. 'Maximum risk . . .' What the hell was a maximum risk in these waters? Did you decide that maybe you'd had enough when the ship was going down because it was overladen with ice, because it had just struck an iceberg? Schmidt, forty-three years old, five feet eight tall and very wide-shouldered, had thick dark hair and thick dark brows. His expression was invariably bleak, not to say grim. And he only smiled in moments of extreme danger, which was the origin of the toast seamen drank to when they had their last beers in a bar in Milwaukee, the Elroy's home port.

'Here's hopin' - no smilin' from the Cap'n till we hit port again.'

'Care to take a look, sir?' Vance Carlson, the mate, stood back from the radarscope and pulled up the collar of his coat. The high bridge of the Elroy was heated but something seemed to have gone wrong with the system. Perhaps the something was the Arctic conditions outside which were keeping a team of men permanently at work shovelling ice over the side, ice which seemed to form as rapidly as they cast it into the floe-littered sea.

Commander Schmidt didn't care to take a look, but he looked all the same. Three hours earlier when he had looked down inside the rubber hood he had seen isolated blips showing on the scope, blips which were not ships, blips to the north-west and north-east. He stared down as he watched the sweep turning remorselessly round the greenish glow inside the hood. No more isolated blips now; instead a solid unbroken pattern of echoes filled the screen, congealing into a wall-to-wall band.

'The barrier,' Carlson commented unnecessarily. 'Dead ahead.'

Schmidt remembered the end of the signal again as he continued staring down into the hood. The barrier. A solid wall of icefield was stretched across his path and the Elroy, its engines beating heavily, its reinforced bow brushing aside great floes of ice like matchsticks, was heading straight for the dreaded wall which stretched from the coast of Spitsbergen to Greenland. The trouble was that Schmidt had to find a way in, a place where the icefield was barely above sea level, a point where he could use the massive bows of the ship to smash his way inside the ice. At least they had the radar to show them what lay ahead. He prayed to God there wouldn't be fog.

Two hours later the menace drifted off the icefield. Fog trails like wisps of steam floated off the ice across the Elroy's path. Schmidt was standing close to the clear-vision panel at the front of the bridge, looking down at the deck and ahead alternately. Neither view enchanted him. The ice on the fore-peak was piling up faster, the new team of men was fighting a losing battle as they heaved it over the ice-coated rails where it toppled down on to more ice drifting on the sea. The temperature was fifty below.

'Polar bears . . .'

At the starboard side of the bridge Carlson was looking at the top of the ice wall which was as high as the bridge itself and no further away than a few cable-lengths. On the fore-deck below men glanced up at the wall above them; it was like looking up the side of a building. In the moonlight three yellowish blurs stared down at them, three polar bears at the brink of the icefield attracted by the smell of the garbage the cook had just emptied overboard.

The engines were dead slow, a regular, powerful throb which reassured Schmidt: earlier they had been badly delayed in their dash back to the north because of engine trouble. The view ahead did not reassure him at all. 'Vance, I think you'd better take a spell in the cage. We don't want to miss our way in .. .'

There was reluctance in the voice which gave the order, a reluctance certainly shared by the mate a few minutes later as he mounted the ice-sheathed ladder up the hundred-foot mast leading to the observation cage. It wasn't the most comfortable post on the Elroy - not in a temperature of fifty below and not with fog coming up. The observation cage at the Elroy's masthead wasn't larger than two telephone kiosks and Carlson experienced his usual sense of claustrophobia as he settled on the leather-topped stool. Thirty-two years old, the same age as Beaumont, Vance Carlson had got married only one day before his ship left Milwaukee. He had been counting the days of the voyage home when the ship had turned round and headed back to the icefield. Like the Captain, the mate did not love Beaumont.

After a quick glance through his clear-vision panel Carlson hitched the harness over his head, adjusted the mike under his chin and checked with the bridge. 'In position, sir. There's a big berg dead ahead.'

'We've seen it ...' Schmidt's voice came up the wire. 'Any sign of an entry point?'

'None at all, sir. It's as solid as a mountain.'

'Keep looking,'

Carlson experienced a sense of claustrophobia inside the cage; perversely he also experienced a sense of being horribly exposed. The walls which surrounded him, which he could reach out and touch with his extended elbows, were armour-glass, and their transparency made him feel, if this were possible, even colder. On the bridge below the heating wasn't totally effective; inside the observation cage it seemed totally ineffective, as though it had lost itself on its way up the mast.

One hundred feet above the deck, Carlson had an all-round view. To port, to starboard, below. The vessel seemed to be hardly moving, the bow slamming into huge floes as big as houses, cube-shaped floes which looked like sugar lumps seen from the cage. The flock of cubes divided, slid past either side of the ship, and beyond them the minor monster loomed, its peak high above Carlson's head, apparently motionless as though anchored to the seabed. But the berg wasn't anchored, it was drifting south, south towards the Elroy while the ship steamed north.

Carlson clubbed his gloved hands together, leaned sideways off his stool as he stared one way, then another. Above where he sat the large radar wing revolved steadily, transmitting its warning echoes to the hooded scope on the bridge. To starboard the ice wall slid past, the polar bears long since vanished. Below the lozenge-shaped deck was so laden with ice that from the cage it appeared to be a fragment broken away from the main icefield. Carlson pressed the send-switch. 'Heavy fog coming up, sir. About a quarter-mile away - dead ahead . . .'

Thirty minutes later Carlson was isolated. He couldn't see a thing. He was also very cold. The numbness which had begun in his feet and hands was spreading. To keep himself alert he was standing up and the four walls of glass were frosted over, coated with a deadly white rime which was growing thicker by the minute. His only view was through the clear-vision panel, and when he peered through this he saw only fog, creeping, ice-laden fog which had blotted out the icefield. Even the deck was invisible and he might have been inside the cabin of a plane in the night.

'You'd better come down, Carlson,' Schmidt ordered.

'I'll stay up a bit longer. It may clear.'

'Fifteen minutes. Then come down . ..'

Carlson pressed his face against the clear-vision panel and the glass was freezing, like pressing into ice itself. He saw nothing. A dense mass of moisture. Nothing more. The vessel was almost stationary, moving at slow-slow speed with the aid of the radar wing above Carlson's head, the metal eye which would throw back a warning echo when an iceberg loomed dead ahead. But the mechanism wasn't foolproof under these conditions and on the bridge below DaSilva, deputy mate and an experienced radar man, was staring anxiously down at the scope, waiting for it to go wild, to ping-ping-ping - warning that something big was close to the bows. The engines beat with a slow monotony while Carlson, the loneliest man aboard, went on staring hypnotically at the fog rolling inches from his face.

'Anything yet, Vance?'

'Nothing yet.'

In the cage Carlson had checked every window when he saw a change in the fog ahead. He couldn't see anything specific, but there was a change, a faint motion as though the vapour was affected by the merest of air currents. He stopped banging his gloves together, stood quite still with his face again pressed into the panel. Yes, there was something, something which was disturbing the fog like a giant spoon stirring it gently.

The warning ping on the scope came too late, too suddenly, and afterwards Schmidt had to speak forcefully to convince DaSilva that there was nothing he could have done. Nothing. It was too quick. On the scope the sweep went round and abruptly there was a new image. DaSilva raised his head, started shouting ...

Carlson probably never saw it coming. If he did it could only have been for a fraction of a second. The ice claw, the huge rampart projecting across the Elroy's path was eighty feet above the deck surface. It stretched out like a gigantic arm, thrust out across the path of the Elroy as though trying to hold it back. The ship steamed on, slowly. The claw came over the bows, over the deck, and the masthead struck it. One shattering, shearing blow. They heard the crack on the bridge as DaSilva had his mouth open to shout a warning, a crack which sent terror into their brains. The masthead was sliced off, eighty feet above the deck. The cage, eighty-five feet up, toppled with the severed mast. Sealed inside the cage, Carlson went down with it. It hit the deck-rail, eighty-five feet below, on the starboard side, smashed away a section, went on down into the sea with Carlson inside it. The severed head weighed five tons and went straight down, taking Carlson and the radar wing with it, down into the Arctic where the depth varies between nine and ten thousand feet. It can only be hoped that the mate was dead before the sea burst in.

The roll of the dead was beginning to mount. Vance Carlson was the twentieth casualty so far - including Nikolai Marov, Gorov's security guard, Tillotson, the sixteen who died aboard the plane on Target-5, and Matthew Conway.

And the radar was gone. The Elroy was blind, engulfed in fog, surrounded by ice, on the verge of the icefield itself, an icefield no one could see. This was beyond maximum risk, far beyond it; if any situation justified Alfred Schmidt in turning round and making slowly for home, this was it.

At Curtis Field the code-signal, 'Oxygen-Strongbow', had been received and understood. 'We have Gorov, we are moving south to rendezvous with the Elroy.'

It was not the only information Dawes had received as he paced round the small office which had been made over to him, an office which glowed with warmth from the three heaters under the windows. The atmosphere was seventy degrees and the warmth caressed his red face as Adams perched on a chair tilted against a wall and watched him.

'The ice west of Target-5 is crawling with Russians,' he growled as he chewed at his unlit cigar. 'They've got choppers over the ice and sled-teams down on the pack - and the Cats are beginning to appear.'

'It looks tricky,' Adams said.

'In Washington you said it would be simple,' Dawes reminded him. He looked up as Fuller, the airfield controller, hurried into the room. 'Time you got here. I want intensive air surveillance over the entire area between the coast and Target-5. I want one third of the machines you send up concentrated on the ice north of Target-5 . . .' He went over to the map he had brought with him which was pinned to the wall. 'Here - and here.'

'Nothing to the south?' Fuller queried.

'Nothing! And I want non-stop surveillance. They go out, they come back, they refuel, they go out again . . .'

'There's a limit to how much the pilots can take,' Fuller pointed out.

'Find that limit - then push them beyond it.'

'I don't get it,' Adams said when Fuller had gone. 'Beaumont's heading south, so why send the aircraft west and north?'

'If you don't get it, maybe Papanin won't. Our chances of spotting Beaumont from the air in the polar 'waste are nil -unless we got lucky. I'm not counting on that. So I'm launching a deception operation.' Dawes paused as the blast of a helicopter's rotor went past beyond the window. 'Papanin has a whole fleet of choppers scouring the ice. In a couple of hours he'll hear of my air surveillance, so what will he assume? That I'm looking for Gorov - that I know where to look. He'll withdraw his machines from the south and that may give Beaumont a chance to get out of range.'

'It could work, I suppose . . .'

'It will work!' Dawes grinned crookedly. 'I'm sending that bastard Siberian a signal - Beaumont is corning out north or west.'

'North or west?'

Papanin muttered the words to himself as he gazed down at his pocket chess board in the headquarters hut at North Pole 17. On the table beside the board was a book open at the page recording the moves in the Fischer-Spassky game at Santa Monica in 1966. The Siberian prided himself on being able to do three things at once: play his own game, study another man's game, and take a decision on the current operation.

'All the machines are in the air,' Kramer reported from behind his chair. 'They are concentrating on the northern and western approaches to Target-5 - all except the six helicopters you told me to hold back.'

After the American Sno-Cat had crashed over the ramp they had paid a second visit to Target-5 and they had found the island deserted. No one was there - although Papanin did not realize that two men, Rickard and Sondeborg, should have still been at the camp. The Siberian had left a small detachment to wait in case Gorov arrived, and had then gone straight back to his own base. Until he received the signal from Petrov at Leningrad Records he had been puzzled.

'The Beaumont force we kept talking about doesn't exist,' he commented as he fingered a pawn.

We? The Bait said nothing. When things went right Papanin invariably referred to events in the first person singular. When trouble loomed there were references to 'we' as the Siberian included him in the mess.

Papanin pushed back his chair, placed one booted leg carefully on the table beside the little chess board, and explained. The signal had come back from Leningrad in reply to his query. The diligent Petrov had buried deep into the massive archives and the mystery was solved.

In 1971 the Americans had sent a three-man team clear across the pack from Greenland to Spitsbergen. The achievement was never reported in the press, but a Soviet agent in Spitsbergen had sent a vague report. The expedition had obvious military implications: in case of real trouble Soviet forces might attempt to occupy Norwegian Spitsbergen - as the Americans had occupied Iceland in the last war. The Americans had foreseen this; if they could send men in over the pack they had a chance of occupying Spitsbergen first, So they had quietly sent a small team to see if it could be managed.

'It doesn't seem relevant,' Kramer protested.

'Doesn't it?' Papanin grinned unpleasantly as he filled his pipe. 'Beaumont is the name of the British Arctic expert who led the team to Spitsbergen. He had two men with him - an American, Samuel Grayson, and a German, Horst Langer. I think that big swine who had so much to say for himself at Target-5 was Beaumont.'

'They wouldn't send in only three men to take out Gorov . . .'

'Wouldn't they? It could be clever, it could be enough. How easy is it to spot four men from the air in the polar wastes, Kramer?'

'So there's no large expedition?' Kramer said dubiously.

'Just Beaumont and his friends. Remember those three men we filmed slipping into the fog two days ago?' Papanin's tone changed. 'Send a coded signal to all planes in the air - they are looking for a very small group. Probably two sled-teams and four men only.'

'And the six machines still waiting?'

'They are to fly south - due south of Target-5.'

'But the Americans are looking north and west ...'

'Carry out my orders immediately,' Papanin said quietly.

Alone in the hut, the Siberian dropped his leg to the floor and frowned as he studied the chess board. Some of his more bizarre decisions he never explained: it was part of his technique for keeping his subordinates in permanent awe of their huge chief. Like De Gaulle, Papanin believed in surrounding himself with a certain mystic aura - it also helped when some of the decisions turned out to be wrong. No one knew what you had been trying to do in the first place.

But Papanin had a definite suspicion in his head, a growing suspicion. During the flight of the Bison bomber from Murmansk he had studied a dossier on Lemuel Quincey Dawes, whose speciality was deception operations. He couldn't ignore the obvious - that the concentration of American machines north and west of Target-5 was indeed searching for the Beaumont group; if it all went wrong he would be severely criticized for not checking those areas. But the southern sector was beginning to interest him.

Kramer came back into the hut a few minutes later. 'They will be airborne within five minutes,' he informed the Siberian.

'Excellent. Now send a signal to the carrier Gorki that I need an immediate check on the position of the American icebreaker Elroy.'

Mystified again, Kramer hurried away to the wireless hut. And again Papanin carefully did not give his reasons. When the Beaumont team was approaching Spitsbergen in 1971 it had made a prearranged rendezvous with the icebreaker Edisto; now another icebreaker was involved, the Elroy. Papanin had an idea he was getting close to Beaumont as he made up his mind and moved the pawn.

Beaumont wouldn't listen to reason; perhaps it would be more accurate to say Beaumont wouldn't listen to anyone as he kept men and dogs moving remorselessly, driving them on, refusing to stop for food or drink, refusing to stop for anything or anyone as they moved further and further south down the tenth meridian and closer and closer to the edge of the icefield, to Iceberg Alley.

Hemmed in by pressure ridges, huge walls of jagged ice which loomed all around them, they sledded south down the ravines in the moonlight. And Beaumont had now taken over Langer's team, had the powerful Bismarck as his lead dog as he gripped the handlebar and cracked his whip over the dogs' heads. Which was an unmistakable sign that they were going to be driven to their limits as Langer observed to Grayson - to their limits and beyond them.

This was what had happened during the last stages of their drive over the pack to Spitsbergen and their rendezvous with another icebreaker,', the Edisto. Beaumont had taken over the Bismarck dog team and they had never let up for twelve hours - not until the Edisto was in sight, the Elliott homing beacon had been switched on, the radio signal had been sent and the chopper from the icebreaker had come winging towards them. This time it was Langer who started the argument, who thought that Beaumont had over-reached himself. He handed over his sled-team to Grayson, ran ahead down the ravine and caught up with Beaumont.

'I don't think we can keep this up much longer ...' he panted.

'Keep moving!'

Beaumont, his face set inside the narrow aperture of fur hood, cracked the whip, coaxed a little more speed out of Bismarck and the other animals increased pace. They came to a bend in the ravine but Beaumont didn't slacken pace; he took the sled round on one runner and it scudded over the hard ice.

'This is crazy,' Langer blazed. 'We need some rest - the dogs need some rest. The Elroy is miles and miles away. We can't possibly make it tonight. ..'

'We have to keep moving, for Christ's sake! Every half-mile is a half-mile closer to the Elroy. It's better than that -the bloody ship is moving towards us!'

'Gorov is feeling the strain.'

Beaumont glanced quickly over his shoulder. Behind him Grayson was driving the second team, forcing them to keep up with Bismarck - and Beaumont. Behind them the Russian followed on foot, his teeth gritted as he fought to keep up with them. It was a deliberate, brutal act of policy on Beaumont's part to put him at the rear; travelling on a sled he slowed everything down, but following them on foot Gorov was constantly afraid that he would be left behind, lost in the polar waste, and his fear of being left was keeping him moving, was forcing him to summon up reserves -of energy he didn't even know he had. 'He'll move if he's scared,' Beaumont had said three hours earlier, 'so keep him scared.'

'He knew it wouldn't be any picnic when he left North Pole 17,' Beaumont snapped. 'Don't talk to him - I want him running scared. And don't talk to me -I have to watch this sled.'

Langer dropped back: Beaumont was in one of his foulest moods, you couldn't reason with him any more. They'd just have to keep moving. But Beaumont's temper was under perfect control: he had simply chosen the simplest method of shutting Langer up. And his grim rush across the ice was based on cold calculation. For three hours they had seen no sign of a Russian helicopter. Why, he had no idea, nor did he care, but now the moonlit sky above the pack was clear of the enemy he was determined to make the most of it, to get as far south as possible while they didn't have to worry about hiding from Papanin's eyes in the sky.

Nor had he thought it wise to reveal to the others that if humanly possible they were going to keep moving until they sighted the Elroy. For some unknown reason they had been given a golden opportunity to get clear, an opportunity which might never recur. Privately he doubted whether they would sight the Elroy that night, but it wasn't an impossible hope and he was going to drive them until they dropped. An hour later the American plane appeared to the southeast.

'Halt!'

Beaumont jerked up his arm to warn those behind him and it felt like jerking up a heavy weight. He pulled at the sled to stop the dogs, handed the whip to Grayson, then forced himself to start climbing the pressure wall to his left. His fatigue was so enormous it felt like climbing a mountain and as he clawed his way up the ice wall the distant murmur of the machine's engine urged him to hurry, hurry. It was a different sound, not the deadly beat-beat of a Soviet helicopter. Once he slipped but his clawing gloves saved him as he grabbed at the crest of the ridge and hauled himself over it. The night-glasses slung round his neck struck his jaw but he was hardly aware of the pain as he sat astride the crest and raised the glasses.

They were almost out of the pressure ridge maze: just ahead of them the frozen sea stretched away like a level plain; very much like a frozen sea with ripples congealed on its surface. The plane, two thousand feet up, was flying south-west and would soon pass them at a distance of about half a mile. He fumbled with the focusing mechanism. Russian or American? The silhouette came up as a blur, so he thought he had the focus wrong, then he realized it was his tired eyes. His eyes cleared, the machine crisped in the lenses, a white star painted on its fuselage. American!

'Sam! Get a smoke flare off my sled. It's American .. .'

The exhausted men down in the ravine were galvanized. Grayson tore open the fastenings, Langer grabbed a flare while Gorov watched the dogs, climbed halfway up the ice wall with the flare which Beaumont took from his extended hand. His fingers were so frozen he had trouble dealing with the flare. He tried to set it off, tried again. Nothing happened. 'Give me another,' Beaumont shouted. 'This one's a dud

There was a frantic scramble as Grayson and Langer struggled to locate a second flare, and while they searched, the plane with red and green lights at its wingtips began to turn, moving in an arc which would take it on a fresh course due south. 'Hurry up, for God's sake!' Beaumont roared. He saw that Grayson had found a flare, was going to bring it up to him. 'Set it off down there in the ravine!'

The flare ignited, gushed dark smoke, climbed in the still air like an Indian signal, billowed, went higher and higher. And the plane went away, continued south, growing smaller and smaller by the second. Grayson and Langer scrambled up on to the crest beside him.

'It hasn't gone .. .'

There was anguish in Grayson's voice, crushing anguish, and his shoulders sagged. 'Look back, you bloody fool,' Beaumont said quietly. They watched the plane to vanishing point. A silver pinhead in the moonlight, it disappeared suddenly, leaving behind only the fading sound of its engine. 'It was a routine weather flight,' Beaumont observed, 'they weren't looking for us.'

'I would like to shoot the Goddamned so-called observer in that machine,' Langer said with quiet venom. 'Maybe we should have used the radio.'

'No!' Beaumont's tone was sharp. 'We're not using that till we're within range of the Elroy. At this very moment there will be a Soviet monitor crouched over his set waiting for us to do just that - so he can take a radio-direction fix. We'll get moving.'

The smoke flare climbed above them as they moved off in silence. Even the dogs seemed subdued, felt to be pulling the sleds with less vigour as they emerged from the pressure ridges and went out on to the plain of ice. Afterwards Beaumont blamed himself for not thinking of the danger, for taking them out on to the exposed ice too soon, but the disappointment and the fatigue had dulled his brain. His arms and wrists were aching with the strain, felt as though they were on fire, half-pulled out of their sockets after hours of wrestling with the bucking sled. The numbing cold was weakening his grip on the handlebar, he had to make an enormous effort to keep tramping forward with an appearance of vigour, to keep the others moving.

'Look out!'

It was Langer who shouted the warning. 'Keep still!' Beaumont shouted his own warning as he brought the dogs to a sudden halt. Behind them the night was shattered with a beating roar. Rat-tat-tat throbs echoed across the ice. The nose of the shadow was bulbous with a second, smaller bulb below it. Twin rotors whipped the air, one above the other. A double-finned tail. Like an evil metal bird it swept over their heads at fifty feet, the ground shadow slicing over the ice. A twin-jet submarine killer. The latest Soviet helicopter.

'Don't move!'

Beaumont reinforced his warning as the machine flew away from them, climbing now and beginning to turn. There was a chance that the men inside the Russian machine hadn't seen them. Moving at fifty miles an hour -Beaumont's estimate of the helicopter's speed - flashing over the ice where it had suddenly burst upon them from behind the pressure ridges, a Soviet observer would need sharp eyes to spot them. Seconds later he knew that sharp eyes had looked down on them from the machine. It was coming back. It was the smoke flare which had caused the disaster: the flare the American plane had never seen had guided a nearby Russian machine to them.

'What the hell is he going to do?' Langer asked.

'Depends how many men he has aboard,' Beaumont replied tersely.

It was travelling slower - and higher - coming in at least two hundred feet above them. So they had not only spotted the sled teams, they had also seen the rifles looped over the men's shoulders. Beaumont handed over his restless team to Grayson and stood a few yards away, his rifle in his hands. The oncoming submarine killer was a menacing shape, all bulges and rotors, and when it was almost above them it began hovering while its drumbeat hammered the ice. Beaumont hoisted his rifle.

The helicopter ceased hovering, banked and began swinging in a wide circle, trailing a gauze of vapour in the cold atmosphere. They had to swing on their heels to follow the helicopter as it went round them, its engines drumming away. Then Langer grunted, hoisted his weapon. 'They've got a telescopic sight on us . . .' Looping his rifle over his shoulder, Beaumont snatched up his night-glasses,

'Drop that rifle!' Beaumont spoke quickly as he continued watching the machine through his glasses, pivoting on his boots. A window had been lowered in the dome and the moonlight reflected off something with a cylindrical muzzle. 'It's a cine-camera,' Beaumont warned. 'They're taking pictures of us - a nice peaceful occupation. With a telephoto lens.' he added.

As he spoke the helicopter turned away, presented its double tail-fins towards them and flew off to the north-east. The beat of its twin rotors was fading rapidly as Beaumont ran back to his sled and took over from Grayson. 'I can't figure why it didn't land,' the American said.

'My guess would be they hadn't enough men aboard.' Beaumont stared across the belt of level ice into the distance where more ridges reared up like hill ranges. 'And now we really have to get moving before they catch us in the open again. Because when the Russians do come back they'll have more than enough men.'

'Hold that frame!'

The Siberian's voice roared in the silence of the smoke-filled hut, a silence broken only by the whirring of the film projector. The operator stopped the machine, the image on the screen froze, the image of four men staring up at the camera, one man with a rifle, another man aiming a pair of glasses. A bloated shadow crossed the screen as Papanin stood up and pointed, his shadow fingertip touching a man holding the handlebar of a sled.

'That's him,' Papanin rumbled. 'That's Gorov. I'll bet my pension on it.'

'You can't see his face,' Kramer objected from the darkness. 'You can't see any of the faces . . .'

'Bugger the faces! I watched the way this man moved, the way he cocks his head to one side. That's Gorov, that's our target.' The enormous fingertip shadow moved, touched the fur-clad figure with glasses. 'And I think that's Beaumont. The other two must be Samuel Grayson and Horst Langer.'

'We recall all the planes from the north and west?' the Bait asked, anxious to anticipate the next order.

'You switch on the damned lights in this hut first,'

Papanin said softly. He looked round at one of the men sitting behind him. 'Vronsky, you can find them again?'

The twenty-eight-year-old Russian who had led the security detachment brought from Murmansk stood up and went over to a wall map. Small, lean and mournful-faced, Andrei Vronsky had lost both his parents a month earlier when they had tried to drive over the frozen Volga near Stalingrad: the river had cracked and swallowed them up. 'Here, Colonel,' he pointed to the cross he had drawn. 'We took a star-fix ...'

'So you are confident?'

'We did find them . . .' Vronsky stopped speaking when he noticed the Siberian's expression.

'You found their bloody smoke flare!' Papanin roared. 'You saw it from five miles away and changed course - you said so when I questioned you. God knows why they let off that flare - maybe it went off by accident.'

'I suppose we were lucky ...'

'So I'll show you how to be lucky again!' Papanin took the pencil off Vronsky and stared at the map. 'They are heading for a rendezvous with the American icebreaker Elroy which is here. Draw a line down from Target-5 and you see they are moving down the tenth meridian.'

'So we fly down that...'

'You shut up or listen! They will change direction for a while to throw us off the scent - they'll go either south-south-east or south-south-west.' Papanin drew two slanting lines from the south to the point where Beaumont had been seen. 'Later they will resume their course due south. Allowing for star-fix error, for ice-drift, you will find them inside this triangle. Understand?'

'It makes sense, Colonel .. .'

'Everything I say makes sense.' He looked over his shoulder at Kramer. 'This time every machine must carry a section of armed men.'

'We haven't enough for all the machines.'

'Who the hell said we were going to withdraw all of them - and immediately warn Dawes that his deception operation has failed? I'm. leaving half the pieces on the board to the north and west of Target-5. The other half come back here, refuel, and then scour my triangle.'

They left the hut quickly before the Siberian could comment on their slowness while Papanin remained staring up at the wall map and sucking at his little pipe. 'I think I've got you this tune, Mr Beaumont,' he said to himself.

It had become a nightmare: Russian machines were within hearing all the time. Sometimes the deadly rat-tat-tat beat was a long way off, little more than a murmur in the bitterly cold night as they dragged their weary limbs down more ravines, under the lee of more pressure ridge walls, but even when it was only a murmur you had to listen hard, to concentrate - so that you detected the moment when it started becoming louder, when it was coming in your direction.

At other times it was close, far too close for comfort, the wicked beat rising to a loud cacophony which echoed along the ravines and reverberated over the icy crests. It was, Beaumont admitted to himself, only a matter of time before they were seen - unless they were incredibly lucky. It was only a matter of time because, despite the frequent requests of Grayson and Langer, he obstinately kept them moving -and movement can be seen from the air.

The constant need to listen, to stay on the alert, was now wearing them down as much as driving the sleds, driving their own legs to keep on the move. By ten in the evening the four exhausted men were moving like automatons, their limbs sluggish, their eyes half-closed with the fatigue and the cold, and Gorov had twice said he couldn't go any further, that he must travel on one of the sleds. Beaumont's reaction had been quick and to the point. 'You'll either keep up or die on the ice.'

'But this is why you are here!' Gorov had protested as he stumbled alongside Beaumont's sled. 'You came to collect me!'

'It's got beyond that now,' the Englishman had told him grimly. 'It's a question of our survival - so keep up or drop, I don't care which any more.'

When Gorov had dropped back Beaumont sneaked a look over his shoulder, and the Russian was plodding on beside Langer's sled while in the distance Grayson was completing another star-fix. Beaumont had no intention of leaving the Russian behind; if he collapsed he would have to be carried on a sled. Oddly enough, faced with the prospect of a lonely death on the ice, Gorov was able to keep going.

But the real havoc was played with their nerves and tempers, and now it was becoming dangerous for one man to speak to another because whatever was said it was always the wrong thing. It was just after ten o'clock when Grayson decided that he had had enough, that they had run out of luck, that this time they had to stop before Beaumont's madness destroyed them all. He finished packing the sextant back inside Langer's moving sled and hurried to catch up with Beaumont.

'Another plane coming up - from the east. I'm getting on top of a ridge to check . . .'

'Conserve your energy,' Beaumont snapped. 'It's a long way off...'

'It's coming this way! It's louder already. Do we wait till the bloody thing is on top of us?'

'Yes!'

'Why, for God's sake?'

Beaumont took a tighter grip on the handlebar, and there was barely suppressed fury in his voice as he replied.

'Because we are not playing their game - Papanin's game. Haven't you grasped what's happening? These are random flights - crisscrossing the ice.'

'One of them will spot us .. .'

'If he's lucky, yes. But he'll have to be damned lucky to spot us down inside these ravines. To do that he'll have to fly direct overhead. When that's going to happen we freeze against the wall - I've already hammered that into you.'

'It may be too late then.'

Beaumont took a deep breath, stared at Grayson, then grabbed at the sled with both hands as it nearly toppled sideways. He spoke in a cold, deliberate monotone. 'We have to get further south than Papanin thinks is possible before we rest. These planes are looking for us, yes. But they're also trying to wear us down, to make us stop every time we hear one, so that we never get a chance to reach the Elroy...' He stiffened as the rat-tat-tat he had been listening to while he talked loudened to a roar. 'Get under cover!' ,

They stopped the dogs, sprawled beside them to calm the animals, crashed down full length on the ice and seconds later the helicopter boomed over them, the hellish clatter of its engines deafening them. It swept over them from east to west, flashed across the ravine two hundred feet up, then it was gone. They remained perfectly still because they didn't know yet whether they had been seen. If they had, it would come back. Dropping prone on to the ice shook each man badly, muffled as they were in their layers of clothing, because prone they didn't feel like getting up again. They lay in the ravine alongside their twitching animals, calming them, their bodies frozen, their resistance very low indeed. When the machine didn't come back they clambered slowly to their feet and Grayson tried once more, croaking the words.

'Keith, we ought to stop ... to eat.. .'

Beaumont shook his head slowly, listened, and couldn't hear the sound of any machine. Painfully, he began to climb up the nearest ice wall, slithering back several times before he got anywhere near the crest. It was time to check the view ahead. Once more. Reaching the top, he nearly fell backwards, but regained his balance. He rubbed at the lenses of his night-glasses to clear them, perched his elbows on the crest, raised them to his weary eyes. He could see a long distance, a very long distance indeed. He scanned the blurred horizon, dropped the glasses a fraction, stared through them steadily, then lowered them as he looked down into the ravine. 'I think you'd better come up here," he said quietly.

'Well?' Papanin demanded.

'Nothing yet.' Vronsky closed the door of the hut. 'I've just come back - it looks pretty hopeless.'

'Hopeless, did you say?' Papanin stood up slowly from his chair and Kramer, who knew him, took an involuntary step away from the Siberian. 'You're gutless, Vronsky. You're not fit to lead a detachment. In this game it's the man who goes on longest who wins. I'll have to consider your position when this is over. You were going to eat? Skip the meal, Vronsky - you're aboard the next helicopter that takes off.' He waited until the Russian had left. 'It's going to be difficult if they reach the Elroy, Kramer,' he remarked.

The Bait was startled. It was the first time Papanin had even suggested that Beaumont might reach the ship. 'Difficult?' he queried. 'Impossible once Gorov is aboard an American ship . . .'

'Not impossible, but difficult, yes.' The Siberian's tone was deceptively quiet. 'The thing would begin to assume huge dimensions. Our people back home would start fretting - because of the American President's visit to Moscow in May.'

'We may be lucky . . .'

'I make my own luck!' Papanin's fist crashed down on the table which was now bare: the little chess set was inside his pocket. 'We are changing our tactics,' he rumbled. 'From now on "we sweep north from the Elroy - we'll meet them coming in over the ice. When a machine finds our target it lands as close to them as possible -I don't care how bad the ice is under them.'

'And if the men with Gorov resist?'

'This is the second order you will issue at once. Give it personally to each leader of the armed parties - the pilot must not hear you. We don't want the men with Gorov -they are an embarrassment, so lose them. Bury the bodies under the ice - if an open lead is available drop them into it. The dogs must be killed as well - poisoned meat would be best. And lose the sleds. By midnight, Kramer! Earlier if possible ...'

It had to be a mirage, Beaumont thought when he first saw it in his night-glasses. The image blurred, went away, then came back again as he readjusted the lenses to their original fix. He called down to the men inside the ravine. Langer reached him first; caught by something in Beaumont's voice he mounted the ice wall quickly, then flopped beside the Englishman on the crest. His face was whiskered as he pulled open his hood to use the glasses, whiskered and still smeared with fog streaks many hours old.

'Over there. The thing sticking up.'

Beaumont pointed and Langer, his fingers trembling with anxiety, tried to get a fix. For another three miles ahead the terrible jumble of pressure ridges continued, like a stormy sea with massive waves coming towards them, a stormy sea frozen suddenly in mid-fury. Beyond this was level ice, very level ice indeed, a vast sheet gleaming in the moonlight. In the middle of it was the mirage, something which, if photographed, would look totally unreal. 'Good God!' Langer muttered the exclamation and fell silent.

The mirage was a high-masted ship with a high bridge, a ship made of ice and snow, almost like an unsuccessful wedding cake. In the night-glasses Langer saw that its bows pointed towards him, that it was crusted and coated and mired with ice so that in the moonlight it glittered like a ship made of glass. Icicles hung from the crosstree, from the jagged tip of the mast. Its rails dripped a curtain of ice like the edge of a counterpane flung casually over the foredeck. The bows were very high, as though mounting a huge wave, but the vessel was absolutely stationary, embedded in the pack, and the only clue that it might not have been abandoned was the lights at the tips of the crosstree. It was not a mirage. It was the American icebreaker Elroy, ten miles from the nearest ocean, hemmed in by the pack.

'Good God!' Langer muttered again.

'You said that before,' Beaumont reminded him. 'You must be getting old - you're repeating yourself.'

'I feel old.' Langer corrected himself. 'I felt old! Hey, Sam, it's the Elroy!'

Leaving Gorov to watch over the dogs, Grayson had hauled himself up on to the crest. 'Don't kid me,' he croaked. Langer handed him the glasses. 'See for yourself.' The American opened his hood, exposed an equally haggard, grizzled face, and focused the glasses.

'How the hell did it ever get in so far?' Langer wondered.

'Guts,' Beaumont said. 'I've never met Schmidt, the captain, but he's smashed his way through that stuff inch by inch to get in close to us. The funny thing is I can't see his radar.'

'I do know him,' Grayson said quietly. 'He's a number one bastard - and that's why he's here. How close do you reckon he is?'

'Seven miles away at a guess,' Beaumont replied. 'Any objections to us pushing on?'

They pushed on for two miles at a speed they hadn't achieved for hours, threading their way through the maze of ravines until they were within one mile of the open ice. And because there were still no Russian choppers in the sky Beaumont decided that now they could send the signal and activate the Elliott homing beacon which should bring the Elroy's helicopter over their heads.

It was very cold, colder than ever it seemed, but this could be their overwhelming fatigue. And it was still clear, clear except for the plume of steam-like vapour which hung over the sled-teams as they moved forward, the vapour which was breath of dogs and men condensing in the bitter atmosphere. Unlike the popular conception of the Arctic, screaming blizzards were rare in this latitude; it was simply one of the coldest places on earth.

They halted inside a ravine. Grayson had pointed out that no helicopter could land in this mess but Beaumont had told Langer to unload the transmitter. 'They can winch us up, Sam, one by one,' he explained, 'then I'll take the dogs out on to the open ice.' Langer was unfastening the canvas flaps round the transmitter when Gorov came down the ravine, moving so quickly that Beaumont watched him in surprise. The Russian was breathing heavily as he stopped and spoke almost hysterically. 'Now we are safe I demand you return my property immediately!'

'What the hell are you talking about?' Beaumont was looking down as he spoke, gently heeling his right boot into the ice. It didn't feel too hard and he suspected that the pressure ridges on either side had only recently been formed by the closing of a lead.

'My core! You stole my core! One of you stole it!' Gorov was getting excited as he pulled out the heavy tube from his parka and waved it in Beaumont's face.

'You're holding it,' Beaumont said. He frowned again as the heel of his boot suddenly sank a few inches. When he pulled it came up with an oozing plop. Soft ice. Gorov was too absorbed to notice anything wrong.

'This is not the same core ...'

'You mean the other one had the Catherine charts inside it?' Beaumont was staring directly at Gorov. 'As you said, we may be almost safe. Not a good time to start shouting the odds, is it?'

'The odds?'

'Go back and give Horst a hand with that set.'

Langer had hoisted the man-pack transceiver over his shoulder and was now a long way back down the ravine, carrying it to a more level section before he set it up. It was almost too much for him in his weakened state but he plodded on and then found a level gap in the wall. He put it down carefully as Gorov raved on in the distance.

'I must have my core! It is that core which makes me valuable to Washington ...'

Gorov was still waving the metal tube about like a blunt instrument when Grayson took it off him. 'Valuable?' the American said. 'Until we reach that ship not one of us is worth a bent nickel. We may not have heard one of your choppers for over an hour, but we're not on board that ship yet. Now, give Horst a hand with that transmitter when he's finished.'

'Ground's sticky underfoot, Sam,' Beaumont murmured as Gorov went back up the ravine. 'We'll have to watch it.'

'I suppose it figures,' Grayson replied as he fondled Bismarck to keep him quiet, 'we're getting close to the sea . ..'

They heard the Russian shout, looked along the ravine, saw him falling. He crashed full length along the ravine, tried to get up, fell down again, 'Christ!' Beaumont snapped. 'He's twisted his ankle.' Langer was ready to transmit, had the telescopic aerial extended, and he was just moving the set to a more level patch of ice when he heard the shout. Swearing, he left the set and went down the ravine to help the Russian.

Gorov had twisted his ankle. He tried to stand up a second time and collapsed as Langer reached him. The German grabbed him under the armpits, lowered him to a sitting position with his back to the ice wall, then noticed the boot of his right leg, the one which had brought him down. Black ooze clung to the boot, ooze which was already freezing. 'Keith! Soft ice here - and Gorov can't walk . . .' With Grayson to help him, he formed an arm cradle and they carried Gorov back to the sled where he settled himself, looking anywhere except in Beaumont's direction.

'Better hurry up with that signal,' Beaumont said.

Langer and Grayson went back up the ravine slowly, careful of where they placed their boots, and when Langer reached the gap in the ice wall he stared, wondering if he was going mad. Then he let out a shout which brought Grayson running. The Redifon set had sunk. The main part of the transmitter had vanished and only the disappearing aerial still showed above the surface as a froth of bubbling ooze closed over the box. Langer dropped to his knees, scrabbled desperately in the icy mess, but the box had gone below the level his gloved fingers could reach. In despair he grabbed at the aerial. A piece snapped off and he was left holding it as the rest of it went down. It was gone. They had lost their only means of communicating with the Elroy.

'You have dealt with the caviar?' Papanin demanded.

The Siberian had a new temporary headquarters, a mobile headquarters a thousand feet above the pack as the submarine killer flew steadily south. And he was talking to Vronsky in another machine much further south, using the code-word caviar, for Elroy because he was talking direct on the radio-telephone.

'The caviar is sandwiched,5 Vronsky replied.

Papanin grunted as he switched off and stared down at the icefield below. It was getting close to some kind of climax in the game and he wanted to be there to direct the moves himself. 'By midnight we'll have them,' he said.

'They haven't been seen yet,' Kramer pointed out, ever pessimistic.

Papanin frowned ferociously to shut him up as static crackled in his ear. He listened with an expressionless face, acknowledged the new message, then glared at the pilot. 'Get this thing moving,' he said coldly, 'or are you anchored to the ice?' He turned round and stared at Kramer who was perched on a flap seat at the back of the cabin. 'By midnight, I said. They have just located the target.'

'Keith, the bastard's coming in to land!'

'I expected that.' Beaumont stared up from the top of the ice wall while he watched the submarine killer dropping, both rotors moving more slowly as the machine came down vertically to a point on the level ice a quarter of a mile from where he crouched.

They had been spotted. The helicopter now landing had flown over them twice, and it was landing between them and the icebound ship. He lowered his glasses. Papanin never missed a trick: a second helicopter was hovering over the ice-encrusted silhouette of the ship, poised over the launch pad so Schmidt couldn't send up his own machine.

'We were nearly there,' Grayson said bitterly as he crouched beside Beaumont. 'Another couple of hours and we'd have made it . . .'

'Might as well be a couple of hundred^' Langer said from the other side of Beaumont. He slithered back inside the ravine quickly as the dogs started jumping about. The beating roar of the descending machine echoed along the pressure ridges which crisscrossed the ice in all directions. It touched down, its rotors still whirling. A door opened and men began dropping to the ice, men with rifles. Furry and hooded in the moonlight, they spread out in a broad crescent and began advancing towards the pressure ridges. Again the speed of the operation impressed Beaumont.

'I didn't know that machine could hold so many,' Gray-son said grimly.

'You know what you have to do,' Beaumont reminded him. 'Keep a close eye on Gorov - I don't want him panicking at the psychological moment.'

'You're committing suicide . . .'

'We'll die if we just wait for them. They want Gorov and we're expendable witnesses.'

Beaumont slipped down the side of the ice wall, trailed his rifle and began running down the ravine. Behind him the others watched him go until Grayson gave them a sharp order. Despite the fact that the ice walls on either side towered above him Beaumont ran in a stoop, ignoring the fact that there could be soft ice ahead, praying that the ground would stay firm. In the emergency the fatigue had temporarily left him; he was clear-headed and he had complete control over his limbs. It was hardly surprising that Grayson had called what he was trying to do suicide - Beaumont was running straight towards the Russians.

It was not quite as foolhardy an action as it seemed. He had waited to see what came out of the machine, now they were advancing towards the pressure zone, and now he was running towards the approximate centre of the crescent of men he couldn't see. They would come inside the ravines trying to keep their crescent-shaped formation - so when the right moment came the security detachment could close their crescent, encircling their target. It was the element of surprise Beaumont was counting on: the last thing the section leader would expect would be for one of the hunted men to run towards him.

He ran light-footed, making as little noise as possible as he followed the snaking ravine which twisted and turned; from his high point on the crest Beaumont had noted the course of this ravine, and so far as he could tell it eventually led out on to the open ice at a certain point. In places the ice corridor was in shadow, in other places as he went round a corner he ran into moonlight. Soon he would have to slow down because soon he would be close to the incoming Russians. As he ran he heard in the distance the faint humming beat of the helicopter muffled by the ice walls. The pilot wasn't taking any chances; he was keeping his engines going for fear they might never start again in this temperature. He stopped running, began moving very cautiously. He would meet the Russians soon.

Crouched close to the lee of the right-hand wall, he crept forward, noting alcoves he could dodge back into when he heard them coming - if he heard them coming in time. Beaumont was under no illusion that he faced amateurs: the Soviet Special Security detachments which operated in the Arctic were trained men accustomed to operating in sub-zero temperatures. But they weren't too accustomed to moving on foot over the pack. He was holding his rifle in both hands when the fur-clad Russian came round a corner very quietly.

Both men were startled, but the Russian hadn't been expecting to meet anyone so close to the helicopter. He was carrying an automatic weapon over his shoulder and he made a mistake: he tried to unsling it. Beaumont reacted without thinking, swinging the rifle round in his hands so that the heavy metal butt-plate faced the Russian. He slammed it forward at head height. At the last moment the Russian jerked his head sideways and the butt-plate only grazed his jaw, but it was enough to unbalance him, to send his boots slithering over the ice as he fell backwards and Beaumont moved forward.

The Russian hit the ice with the back of his head. The blow was cushioned by the fur hood he wore. Still sprawled on his back, his own weapon dropped and out of reach, he grasped the Englishman's right boot and the hand was large enough to encircle the ankle. The fingers locked and prepared to heave sideways. Beaumont ignored the danger, concentrating on what he had to do. The rifle came down from high up, hammered down on the Russian's forehead, and the force of the downstroke was so great that the butt rebounded. The hand locked round his ankle relaxed, the head flopped sideways and the man lay still as Beaumont bent down and heaved him over on to his stomach. The impact points - jaw and forehead - were now in contact with the ice, so when they found him - if they ever found him - it would look like an accident, an accident caused by the Russian tripping and smashing his face down on the iron-hard ground.

He took an even bigger risk now: he started running again. He had counted about twenty men coming out of the machine and they had to be spread over a rabbit warren of ravines, so probably the arrangement was that when one of them located the fugitives they would open fire to bring the others running. He was still running when he turned a corner and a sheet of light came into view. He had reached the exit - the open ice was ahead.

The roar of the waiting machine's rotors blasted his eardrums coming inside the ravine and he saw it barely a hundred yards away, its double fin facing him, the pilot's cabin looking the other way. It was a point he had noted from the ridge crest and he had been praying the pilot hadn't swung his machine round. He hadn't. And there was no guard waiting at the edge of the ice. It didn't surprise Beaumont; when you have twenty men at your disposal and you go in to capture a group of four men you'd hardly anticipate that one of them would be mad enough to head straight for the machine. Beaumont headed straight for the machine.

He looped his rifle over his shoulder and began walking at a moderate pace towards the rear of the helicopter. It seemed a crazy thing to do, to walk slowly, but Beaumont was gambling on elementary psychology in case the pilot inside the cabin did look behind him. Reflexes moved fast when jerked into action - the sight of an armed man running across the ice towards the machine would provoke one reaction in the pilot. He would pull the lever, take the machine vertically off the ice. A five-second job. Beaumont kept walking slowly, coming closer to the submarine killer.

Beaumont was fairly confident now that he was going to make it; although his fur hood and parka hardly matched the security men's outfit it was similar - similar enough when seen by moonlight through the ice-rimmed dome of a helicopter. As he neared the machine, as the deafening drumbeat increased in decibels, every nerve in his body was screaming at him to run, to cover the last fifty yards before the pilot turned his head. Beaumont kept walking at the same even pace, coming up directly behind the old-fashioned-looking tail, the kind of tail .biplanes had once sported. Unlooping his rifle, he walked past the tail, climbed up and hammered with his gloved fist on the misted dome.

The vibration shuddered him and nothing happened. He beat with his fist a second time and then the window slid open. The rifle went inside at the same moment as warm air wafted in his face, the muzzle pointed at a helmeted figure who had jumped back into his seat behind the controls. 'Get out! Come on! Get out - quick!' Beaumont shouted in Russian and jerked his head to show the pilot what he wanted - with the drumbeat going full blast the pilot probably couldn't hear a word. Beaumont leaned in through the window, jabbed the rifle muzzle hard into the pilot's side. The Russian had goggles down over his eyes but Beaumont had the impression he was young, maybe in his late twenties. Young enough to be a hero. The pilot's right hand moved towards a lever.

The lever, Beaumont guessed instantly, would elevate the helicopter. Suddenly the machine would be climbing and he would be suspended in mid-air, maybe jerked off to smash on the ice below. 'Don't try it ...!' To drive the message home he rammed the muzzle harder into the pilot. The Russian stared sideways and Beaumont read the man's mind. He had guts: he was checking the weapon, wondering whether he could survive the bullet. The calibre must have scared him: his hand moved away from the lever. 'Get up! Up! Up!' Beaumont jerked his head and the pilot disconnected his headset and slid carefully out of his seat.

Something in the pilot's stance warned Beaumont. The Russian paused halfway out of his seat, crouched like a cat, the lenses of his goggles catching the light from the instrument panel so his eyes were invisible. 'Come on,' Beaumont snapped, 'hurry it up.' The Russian came closer as Beaumont withdrew the rifle, cuddling it under his-arm, his finger still inside the trigger guard as he used his other hand to press down the door handle, to slide it open. The pilot spread his hands in a slow gesture of surrender.

But the heroics weren't over yet. The pilot came slowly through the doorway and then he was very close to Beaumont. He turned, as though obeying Beaumont's gesture for him to drop to the ice; then, still crouched under the whirling rotors, he grabbed for the rifle, a reaction the Englishman had anticipated. Beaumont slammed down the butt, struck the Russian on the shin, and the pilot grabbed for the door frame to regain his balance. Holding on to the frame he straightened up on one leg. He came within range of the steel blades of the lower rotor. They beheaded him.

Still crouched and clinging to the window frame, Beaumont was stunned with horror. He swallowed bile. The corpse was below him on the ice. Dark spots flecked the ice around the huddled heap. The head had been hurled God knew where by the whipping blades. It was incredible - a helicopter pilot decapitated by his own rotor - but the majority of accidents happen in the home, and for the pilot the machine had been home. Shaking - and not only from the vibration - Beaumont went inside the cabin and closed the door on what lay below it. Then he eased himself into the pilot's seat and stared at the control panel.

It was not entirely unlike the Sikorsky's control panel. And a year earlier Beaumont had visited the Soviet base, North Pole 15, now orbiting the Pole somewhere off the Siberian coast, where a vodka-filled pilot had shown him his submarine killer before the security man had arrived to drag them both out of the machine. Beaumont had sent a report to Washington and London about that machine and now he desperately tried to recall its details.

The altitude readings were in metres, of course. Most of the dials and levers he understood, but there was one dial and two switches he couldn't fathom. Cautiously he touched the lever the pilot had reached for. Nothing happened. He pushed it a shade further and the machine left the ice. He pulled it towards him and felt the bump as the skids touched down again. The spare helmet he had taken from a hook and put over his head as soon as he sat down was loose-fitting. He fastened it more tightly, clamping the ear muffs closer to cut out the hellish row. The instrument panel was juddering badly but he suspected some of this was his own fatigue. Fiddling with several other controls, he sorted out the set-up calmly, knowing that at any moment the Russians on the ice might reach the sled-teams. But he had to grasp the mechanism of this thing. He opened the throttles and the twin jets boomed. He took a deep breath, operated the ascent lever.

The machine climbed faster than he'd expected, shot up vertically with a drumming roar. When the altimeter registered one hundred metres he hovered, then flew forward. He changed direction, flew through the arc of a circle. Beyond a clear patch in the perspex dome the Elroy appeared like a stranded toy, then vanished. The small lever which had puzzled him banked the helicopter. It was responding to his touch now. Reluctantly. He had a feeling of enormous power locked in behind the panel, power itching to break loose, and in flight the cabin vibrated more than a Sikorsky's, vibrated like an old washing machine.

From above the ridges looked weird in the moonlight, levelled down to ribs of ice like the burial ground of prehistoric monsters, their long-dead bones bleached a pale colour. He saw two men moving along an ice corridor. He ignored them, searching for the assembly point, the strangely-shaped area they had crossed shortly before they heard the Russian machine coming. He sent the sled teams back there to wait for him because it was the only place inside the ridges where a helicopter could land - a tiny amphitheatre of ice, a bowl surrounded with pressure ridge walls. He flew over more Russians who stopped and stared upwards, flew on some distance, then realized he had overshot the amphitheatre and turned.

Beaumont was becoming worried now. If he couldn't find the amphitheatre first the Russians would reach the sled teams, might even have reached them already. He saw other fur-clad figures moving along the ravines, some of them running, and all of them stopped to stare up at him, wondering why the hell their machine had taken off from the ice. And conditions inside the large cabin could have been better: the heaven-sent warmth was counteracted by a smell which kept intruding on his stomach, a stench of petrol fumes which was nauseating. Either there was something wrong with the machine or Russian engine technology lagged sadly behind British and American. Then he saw it - a white circle among the shadows.

He operated the lever and started going down. Three men, two sleds, the dogs were in the middle of the bowl, and one of the men was waving frantically. Then five Russians came over a nearby ridge crest and looked down into the bowl with rifles in their hands. Under the helmet Beaumont's face was grim: he had arrived too late.

Pressing himself hard against the seat back, he banked the machine, lost altitude, increased the revs, flew straight for the Russians. Beyond the perspex dome he saw them standing on the crest, frozen with astonishment. The helmet and goggles he had put on helped the illusion, heightened the tension - because from the crest the five men saw their own machine, piloted by their own comrade, come screaming down towards them.

The row inside the cabin was deafening. The frame was vibrating as though soon it would shake every rivet free from the fuselage. Beaumont increased the revs again and beyond the dome the five men flew towards him. He moved the stick and the machine thundered over the crest, rotors whipping, the skids just clearing the ridge - and the men were gone, tumbling down the far side of the ridge as they took desperate evading action. Beaumont climbed again, turned, saw the Russians on their feet inside a wide ice corridor. He dived, aimed the machine point-blank along the corridor, and the security men, seeing what was coming, fled. Beaumont continued his power-dive, took the machine down dangerously low, levelled out just above the crests, continued on course along the corridor.

The skids missed the men's heads by feet - down inside the corridor it must have seemed like inches as they flung themselves to the ground and the reverberations of the engines pounded their eardrums. When Beaumont looked back they had started to run again - away from the amphitheatre, demoralized. His terror campaign was beginning to work. And it must seem terrifying to the security detachment who were bound to assume their own pilot was behind the controls, a pilot who had gone berserk. The irony was that no one would fire a single shot at him - the machine he was flying was their only transport out of the terrible polar wasteland. He made three more circuits of the amphitheatre and then went down.

His eyes were watering from the petrol fumes which had seeped under his loose-fitting goggles as he descended into the bowl. In his anxiety to get down fast he landed heavily on the ice: it was only a matter of time before the Russians pulled themselves together and then they would be swarming towards the place where they had seen the helicopter landing. Leaving the rotors running, he unfastened his seat-strap, went to the door, opened it. He was rather careful of the whirling blades above his head as he jumped down on to the ice.

'Watch those damned rotors,' were his first words. 'Get the dogs aboard first - if trouble comes we leave the sleds.'

The dogs had already been released from the traces and they scrambled them inside the machine, lifting each kicking animal and shoving it unceremoniously aboard. Beaumont waited a short distance from the machine, leaving it to Grayson and Langer to hoist dogs and Gorov inside while he stared round the circle of crests with his rifle ready. The sleds went on board last, and when Beaumont followed them there was no trace left on the ice that the Beaumont party had ever existed.

Beaumont went straight up to a thousand feet, taking them out of range of rifle fire before he set course for the Elroy. Langer stood close to the transparent dome as they climbed, hemmed in by whimpering dogs. He pointed downwards. 'We were only just in time.' Beaumont nodded. A group of six Russians was moving close to the amphitheatre as they ascended.

From their altitude of one thousand feet the Elroy looked like a ghost ship, one of the legendary vessels which drift round the oceans of the world without a crew, a ghost ship set in solid ice. As they came closer Beaumont saw a channel beyond its stern, a dark slash of sea where the icebreaker had battered its way through the polar pack, but beyond the slash there was continuous ice. As the ship hammered its way north the icefield had closed behind it, locking it in.

'That other sub-killer is still hanging over the ship,' Langer said suddenly.

'I know,' Beaumont replied. 'We're going to have to shift it.'

He moved the stick and they started losing height, close enough to the ship to see men running to the rails and staring up as a second Russian machine homed in on them. And some of the seamen carried rifles. Aft of the high bridge, close to the stern, they could see now far below another helicopter, a Sikorsky, resting on its launching pad while the Soviet machine clung to the air above it. So long as the hovering machine held its present position it was impossible for the American plane to leave its pad - it would have ascended directly into the other machine. 'I suppose that other sub-killer thinks we're his pal,' Grayson remarked as he patted one of the dogs.

'He's in for a shock,' Beaumont said tersely.

'They may try to crash us . . .' Gorov who had sat in silence on a folding seat at the back of the cabin was now alarmed enough to speak. He stood up to get a better view, holding on to a rail to take the weight of his injured ankle.

'Sit down, Gorov!' Beaumont shouted. 'Didn't you hear what Grayson said? The pilot will think we're Russian, which gives us the edge.'

'Two pairs of rotors whirling close together, Keith,' Grayson warned. 'We could end up with both of us taking diving lessons . . .'

'I want that machine out of the way,' Beaumont insisted. 'I want it out of the way before we land . . .' He was almost over the ship now, flying slowly at an altitude of five hundred feet while four hundred feet down the other submarine killer maintained its hover, hanging over the Sikorsky like a threat. The ice-coated rails of the ship were lined with seamen now, all of them staring up at the new arrival, wondering what was going to happen. Standing close to the dome, Langer stared straight down on the machine below, saw the dizzy circle of its rotors whipping through the night, the gauze of vapour spiralling up towards him.

'Keith!' he shouted above the throbbing din. 'Could you take us down slowly alongside that bastard?'

'Yes. Why?'

Langer took down a folded toolkit bag hooked to the side of the dome, opened it, extracted a large steel monkey wrench. 'With our window open I might get his dome. Then he would . . .'

'Got it - we'll try it,' Beaumont shouted. 'You know I can't get too close to his rotors?'

'I'm ready.' Langer pushed two of the dogs away, took a firm grip on the monkey wrench and opened the window. A blast of icy air streamed inside the heated cabin as Beaumont started to go down. Langer's dark hair flew out behind him as he pushed back his hood to see clearly and leaned out of the window. No one spoke again inside the cabin; Gorov hunched nervously on his flap seat; and Beaumont was acutely conscious that he was handling a strange machine, that he was attempting a dangerous manoeuvre which could easily end in total disaster.

The drop went on as Beaumont took the helicopter down slowly. From the window Langer watched the deck of the Elroy coming up, the line of heads staring towards him, a peaked cap which poked out of the bridge window to look up, but above all he watched the giddy ellipse of the lethal rotors below him, slicing the air, rising up to meet him. So far as he could tell Beaumont was gauging his descent with murderous accuracy - accurate because when he came alongside the second machine his own racing blades should clear the rotors below, murderous because the margin of safety was so small.

Exposed to the bitter night air after the brief spell of warmth, Langer's face was already numb and frozen; his eyelids felt like leaden weights, desperately wanted to close, but he forced himself to keep them open, to stay hanging out of the window. Then he saw the vague shape of the top of a helmet under the dome; as he watched it the helmet tilted and something pale came into view, a pale blur seen under a clear patch in the ice-rimmed dome - the pilot's face watching Beaumont coming down almost on top of him. He had had no signal to leave his post. Now it was too late.

For the Russian the position was reversed. He had successfully immobilized the American helicopter, holding it down on its pad, but now he was sandwiched, unable to go down, unable to climb, caught in a press between the other two machines, and the press was closing, coming down on top of him. Beaumont had hoped that the pilot's nerve would crack, that the slow descent would make him run, and while they had been at five hundred feet the Russian could have escaped. Now it was too late. Caught in an emergency the Russian pilot's nerve hadn't broken, it had frozen. Unsure of what to do, he did nothing. Beaumont's descent continued, the gap closed, the skids of his machine hovered close to the Russian's transparent dome.

They were so close now that the air disturbance was exerting full power, sucking air down, and Langer had the sensation that it was about to tear him out of the window down into the mincing machine of the whirling rotors. He pulled his head in, slammed the window shut, continued watching from inside. The air disturbance was now causing another dangerous reaction - the machine was rocking from side to side. It wasn't impossible that a whirlpool reaction would start - drawing both helicopters towards each other until their rotor tips met in one brief grinding clash. Then they were alongside each other and Langer opened the window again.

There was an observer as well as a pilot in the Soviet machine and Beaumont could see him operating his headset, talking' non-stop as he kept glancing across at them. A signal was being sent to someone. Then Gorov did a stupid thing. Restless with anxiety, he stood up and peered towards the dome of the other helicopter. 'Sit down!' Beaumont roared. He didn't think Soviet pilots were insane enough to use suicide tactics but he didn't know what instructions they had received regarding Gorov. Beaumont held his own helicopter in a hover, ready to fly forward, much of his attention focused on the thick silhouette of the mast which had to be avoided whatever happened. 'OK, Horst,' he shouted. 'Get on with it!'

Below them the deck of the Elroy had cleared suddenly; either by order of the ship's commander or through instinctive self-preservation, the American seamen had disappeared, taken cover. Beaumont watched Horst, his hand on the lever which would take them forward, away from machine, ship and mast in a. burst of speed. The noise inside the cabin was terrible now, shattering as the engines of the other machine added their blasting roar to the din. And the Soviet helicopter was rocking badly too, quaking as though about to split open.

Langer screwed up his eyes to see more clearly, saw the curve of the Russian's dome only yards away. For seconds they wobbled close to each other. Langer leaned well out of the window and was deafened, paralysed with the cold. He raised his right arm, paused, hurled the monkey wrench in a careful arc, slammed the window shut.

The missile struck the shatter-proof dome, a dome shuddering with vibration, hurtled away at an angle into the night. Langer stared through his own dome. It had worked. Shatterproof, the Russian's dome hadn't shattered - it had crazed. No longer transparent, its curved surface was milky - the pilot inside was blind, couldn't see a damned thing. Beaumont shot away from the blinded Russian, banked away from the ship's mast which loomed like a gigantic flagpole, flew on out over the ice.

Every helicopter has a smaller rotor at the .tail. Without a tail rotor mounted at right-angles to the pitch of the main rotor no helicopter would fly. The enormous power of the overhead rotor has a natural torque reaction - whirling through the air it would sweep the fuselage it supports round and round at ever-increasing speed - but for the counter-force of the tail rotor. This was something the Soviet pilot and his observer were about to experience for brief killing seconds.

As Beaumont had anticipated, the Soviet pilot did the wrong thing. It was understandable; it was also fatal. At one moment, sitting behind his controls, the pilot still had a clear view of his surroundings. Then Horst's wrench struck and he was surrounded by opaqueness, by crazed windows he couldn't see through at all. The world went milky on him. He was confined to a view of his cabin. He panicked.

He had to get away from the mast, to fly clear of the ship and out above the open ice where Beaumont had gone. He moved a lever, misjudged it, went forward in a shallow curve, banking to escape the menace of the huge mast. He was only half successful, his main rotors swung clear, but he forgot his tail and curved too sharply. The tail rotor kissed the mast and the whole mechanism left the machine. The balance-force which countered the torque tendency was gone. Basic aerodynamics came into play.

Once in Sydney, Australia, Beaumont had seen a film taken from an automatic camera mounted in a helicopter which flew too close to a building in Sydney Harbour. The tail rotor kissed the building, dropped into the water, and the camera recorded what happened. Later it was dredged up from the wreckage containing two bodies and the film was re-run. It was terrifying. He recalled the film as he saw what happened to the Soviet helicopter, knew with a horrible clarity what was happening inside the doomed machine.

The cabin began to rotate, to whirl like a top, and the two men inside rotated with it ... Faster and faster they revolved on their own axis with the machine still in midair, spinning round and round and round at ever-increasing speed in endless gyrations. In seconds both men were disorientated, powerless, spinning, spinning, spinning. Strapped into their seats, they experienced the full force of the terror, whirling like a roundabout gone mad, at a speed no roundabout out of control would ever attain.

They would have gone mad had it lasted long enough, but it didn't last long enough. The machine lost its equilibrium, banked over sideways, fell towards the ice. The whirling rotors were still hurtling the fuselage round when the smash came. The fuselage broke in two pieces, flew across the ice three hundred yards away from the Elroy as the rotors disintegrated. The fuel tanks detonated, sent out a sheet of flame which melted the ice on the port rails. Black smoke rose and wavered in the breeze which came from the north.

There was another watcher who saw the Soviet helicopter's destruction. Two miles away, flying at three thousand feet, Col Igor Papanin lowered his night-glasses and sat in silence while the pilot beside him waited for instructions.

'What happened?' Kramer asked from the seat behind. 'What was that flame?'

'Shut up! Let me think.'

Papanin was in a state of shock. Only an hour earlier he had flown to where the Elroy was hemmed in by ice to see what was happening. On the way he had received the signal from one of his helicopters: the Beaumont party had been found, men were being landed on the ice to cut them off from the American ship. It had sounded like a triumph.

He had arrived in time to see the Soviet helicopter still hovering over the Elroy. He had sent a signal over the radiotelephone himself, ordering it to keep its position. Then the second machine had appeared. For a few minutes Papanin had no idea what was happening, then the helicopter over the ship had started reporting. For once the Siberian had listened without interrupting, without saying a single word as the communications became more and more tense, climaxing in a report which had chilled him as he listened to the taut words coming through the earphones.

'Machine coming down on us ... several men inside ... window opening . .. Gorov! Gorov! In the machine! ... many dogs . . . three other men .. .'

Then the message ceased. Papanin saw why when he raised his night-glasses and aimed them with difficulty, focusing just in time to see the obscene spectacle of his own helicopter whirling crazily in mid-air before it crashed.

Sitting behind him, Kramer saw the sagging shoulders stiffen. Papanin swung round in his seat and his expression frightened the Bait. 'Send a signal to the Revolution \ Tell them I am on my way. Tell them to start radio-jamming at full power immediately! All vessels! We will establish our headquarters on board the Revolution and wait for the Elroy to come to us.'

'Hydrogen-Strongbow ... Hydrogen-Strongbow ...'

The two-word signal which Beaumont asked the Elroy's captain to radio immediately to Curtis Field the moment he arrived on board reached Dawes close on midnight. 'Hydrogen-Strongbow . ..' The signal told Dawes everything - or almost everything. 'We have Gorov, we are aboard the Elroy.' He asked for a call to be put through to Washington immediately on the hot line.

The hot line went through Curtis Field on its way to Iceland and Europe; the other way it went back through Dye Two, a remote Distant Early Warning Station perched on the icecap, before it continued its long journey to Washington. When the call came through Dawes spoke to a man in the Defence Department and Adams listened, hearing only one end of the conversation.

'Sure we've got Gorov aboard an American ship,' Dawes said at a later stage in his call, 'but for the third time I'd feel a lot happier if we could send an escort ship to take the Elroy home ...'

'No, I'm not suggesting they'd board an American vessel...' he growled at an even later stage.

Two minutes later he slammed down the phone and absentmindedly lit his cigar, the first live smoke he'd enjoyed in seventeen days. 'They won't give her an escort,' he said. 'They say it's all over.' He began pacing the overheated office and staring at the wall map which showed the position of all ships in the area south of Target-5. 'All they can think of is that the President is at this moment in Peking clinking glasses with the Chinese.'

'You lit your cigar,' Adams pointed out. 'You're celebrating?'

'Not yet.'

When Adams had gone to bed Dawes was still pacing slowly, still gazing at the wall map, so uneasy that he knew he wouldn't sleep even if he did go to bed. And in this foreboding Dawes showed more insight than the man in Washington who had said it was all over. It was, in fact, just beginning.

Checkmate

'Take her down! You have to land on that blasted thing one day!'

Papanin shouted the command to make himself heard above the drumming of the rotors as the helicopter hovered uncertainly, hovered over the i6,000-ton research ship Revolution. The aircraft canted sideways, caught by a gust of wind, and Papanin, standing up, grabbed at his seat to save himself. Bloody amateur! The so-called pilots the flying schools turned out these days were a disgrace. Behind the pilot Kramer clung nervously to the flap seat he was perched on: he hated flying and this had been a very rough ride. The pilot regained control of his machine and spoke to the Siberian without looking at him.

'It would be safer if you sat down. Colonel!'

'It would be safer if we were already aboard that ship! Take her down, I said!'

'Landing conditions are very dangerous. I have enough fuel left to stay up .. .'

Papanin sat down next to the pilot in the observer's seat, put his face close to the pilot's, enunciated the words carefully. 'I am ordering you to land on that ship. I have not got the time to hang about in mid-air because you require the sea to be as smooth as a baby's bottom! Take her down!'

He turned away from the pilot and looked down at the ocean. The view was scarcely encouraging. The huge research ship, the showpiece of the Soviet merchant marine, her vast radar dome aft of the bridge gleaming in the moonlight like some strange seaborne mosque, was heaving slowly in a considerable swell. Three hundred feet below them, she rode great sea crests trundling south, her whole structure tilting and then falling, the spike at the top of the radar dome tipping sideways, pausing, climbing again as the seas lifted the vessel. Close to the icefield, ice floes drifted in the surging waves, climbed a crest, slammed down against the bows. The helicopter began to descend.

The pilot, his facial muscles tight, leaned well forward for his first sight of the radar dome. Under these dangerous conditions the dome was his only guide to the whereabouts of the landing pad, immediately aft of the dome. He had to touch the pad at just the right moment; - when it was level -otherwise they would tip over sideways. Spume, caught by the wind, came up and splashed over the perspex, obscuring his view. Feeling the Siberian's stare, he continued the descent. Something like a huge pendulum swivelled beyond the perspex. The masthead, topped by a radar wing. The mast was laden with electronic gear. The Revolution, launched officially as the world's greatest research vessel, was really the Soviet Union's largest spy-ship.

The machine went lower. The dome filled the view now, sliding with the massive sea swell, but the pilot hardly saw it; he was watching the masthead beyond, swinging towards the vertical. When it reached the vertical, paused there for brief seconds, the invisible landing pad would be level. The skids below the undercarriage hit the pad, slammed into it. Waiting technicians rushed forward, clamped the anchor rings tight. The Siberian opened the door while the rotors were still whirling, looked back at the pilot.

'You see! You never know what you can do until you try!5

He jumped to the deck as the pilot glared at him, crouched to avoid the rotors, splayed his huge legs to hold his balance, then he was clawing his way along the rail when the sea sent an avalanche inboard. He clung to the rail, holding his breath until the water receded, and there were frozen spits of ice on his sleeves as he hauled himself up the tilting ladder leading to the great bridge. Captain Anatoli Tuchevsky, the ship's commander, opened the door to let him in.

'Colonel Papanin!' The Siberian, dripping water, took off his sodden parka and dropped it on the floor. 'You are Tuchevsky? Good. A change of clothing, please! Something belonging to the largest rating aboard! Why are you heading north at this turtle pace?'

Tuchevsky, a lean, self-contained man with a beard, grim-faced and thoroughly alarmed about what was happening to his ship, gave an order for fresh clothing to be brought and then led Papanin to the chart-room behind the bridge. He sent away an officer working over a chart with a pair of dividers, shut the door and faced the Siberian.

'I have to protest most strongly ...'

'Protest noted f

'I haven't told you what I'm protesting about yet...'