THE PLOT THICKENED very nicely as the night before Christmas continued.

“I think that Jacob brought this young chick to throw us off the scent,” Claire said. All eyes at our table turned to the quite beautiful Amy Stern, Jacob’s surprise companion for the evening.

Tom nodded agreement. “Think about it. The very sly rabbi shows up with a date—a fabulous-looking date. So everyone thinks, aha. Let’s eliminate him from the list of marriage partners. He’s got a girlfriend.”

“You think Gaby’s so diabolical that she’d go to all that trouble to confuse the situation?” Seth asked. “You think my mom would do that?”

“I do,” said Andie, who had removed her costume’s red nose, thus eliminating the possibility of electrocuting herself during the soup course.

“Unless, of course,” Marty said. “Unless Ms. Stern really is Jacob’s date. Then that would mean that someone else—like Tom or me or even someone we haven’t thought of—is actually going to marry our Gaby.”

“Uh, excuse me, please,” I broke in. “If you don’t mind, this woman in the red silk dress and sapphire necklace is the person you’re all talking about.”

There was laughter at the table, but there was also a sense of “This case has to be solved, Sherlock, and we must do it soon.”

I caught Gus rolling his eyes. When he noticed me noticing him, he did a startlingly accurate imitation of my voice: “Don’t let your first time at the grown-ups’ table become your last time.” He got the inflection, the tone, the style completely right. He had a future, that boy.

While we were laughing, while the soup bowls were being cleared, while a very nice crisp Sancerre was being poured, two missing diners showed up. Full of apologies, only slightly frantic, Emily and Dr. Perfect made their way through the crowd to our table.

“I am so sorry, Mom,” Emily said as she kissed me. “We are such idiots.”

“Really, we are. We heard everybody leaving the house,” Bart said. “And we were all set to go. I was tying my tie, and then…I don’t know…” His voice trailed off.

“I bet I know what happened,” Gus said with a high school boy’s knowing smirk.

“You know a lot more than you need to know,” Claire said as she thumped Gus on the back.

Yes, this was what I was hoping for. The laughs were coming, the wine was flowing, the music was playing. And, of course, the mystery was going strong, stronger than ever tonight. But I didn’t have too much time to savor this feeling of joy.

At the front of the room a ridiculous-looking red-nosed reindeer was tapping a glass with a spoon. From the tail of the reindeer emerged a hand. The hand was holding a microphone.

Uh-oh. The toasts were about to begin.