That night, unable to sleep, I remember a dream I used to have, years ago. Diane’s dad in my apartment, standing on my carpet. The purple swell, the sweat-slick mustache.

Beside me this time, though, is Diane’s mom, her long white scarves, the smell of lipstick.

He’s watching us both, his eyes filled with surprise. His hands clutching his throat, his chest.

Did he ever know what was happening or who was responsible?

What is it like to die from your own heart bursting?

Two, three a.m., I’m lying in bed wakefully, my phone in my hand like a flashlight.

I find myself doing strange things, dragging from the hamper the bedsheets from the other night, looking at them, bringing them to my face and nose.

Where is Alex? I mean the body, not the man. Or do I? None of it seems precisely real any longer. Saturday, he died. Today is Tuesday and he’s still missing. There is no logic to it.

Could Zell or Maxim have found him? Or both of them? But why would they do something with Alex’s body? To blackmail us?

Would someone—anyone—really use blackmail to get a PMDD slot? That’s a question I don’t dare ponder. I don’t even want to think what I’d do for one. What I, in some ways, have done.

At five a.m., the apartment still thick with night, I take my coffee and sit down in the plastic chair, the one with the crack that Diane sat in three days before. I feel something beneath me. When I reach down, my fingers touch something soft.

Diane’s furry key chain. It must’ve come loose from her keys and fallen here. I see now that it’s a tiny rabbit’s foot. Just like the one she had all those years ago, dangling from the keys to her grandfather’s enormous truck.

I hold the foot, rub it with my thumb. Now I know why Diane was always stroking it.

I put it in my pocket, thinking I might need it today.

Two police detectives are in Dr. Severin’s office when I arrive. A ruddy-faced young man and a petite woman, both in raincoats. It’s not because they are movie detectives, as Zell whispers to me, faking a dramatic cigarette puff, but because it’s been raining since late last night.

Dr. Severin emerges from the office, shuts the door behind her.

“They want to talk to everyone,” she mutters to Ilene, standing over Ilene’s immaculate desk, forever gleaming with lemon polish. “They have a list.”

Ilene looks at Severin over the top of her glasses, shaking her head.

“This is very obstructive,” Dr. Severin adds.

“It is,” Ilene says. “It really is.”

Several feet away, I’m at the copier, Xeroxing log sheets. This is bad, I’m thinking. But how bad is it?

“And the dean’s idiotic champagne toast for the grant award is today.” Dr. Severin plucks at the stiff leather pleats on her collar. It’s the first time I’ve seen her fidget with her clothes. The only time I’ve ever seen the shine of sweat at her temples, on her brow.

“Yes, at three.”

“Three o’clock so the dean can go straight from his martini lunch to his cocktail hour,” Severin says. Then, voice lower: “How long do they intend to be here?”

“They wouldn’t say, Dr. Severin.”

“I’m not letting some postdoc’s runaway-groom routine distract us.”

“No, Dr. Severin.”

“Did you guys talk to them yet?” I ask as I walk into G-21. Maxim shakes his head.

“And Juwon called in sick,” Zell says, rubbing the flocked front of his favorite fluorescent-green YEAH, SCIENCE T-shirt. “We’re dropping like flies.”

“My bet is Juwon’s interviewing across the river,” Maxim says, walking toward the supply cabinet. “Or maybe he’s on a plane to Freudlinger, gunning for Diane Fleming’s old job.”

With Maxim’s back turned, Zell beckons me over.

“Maybe Maxim figures if he can wait it out,” Zell whispers, the smell of ethanol and salami coming off him, “you or Diane might disappear into the ether too and he can get your slot.”

I look over at Maxim, who’s staring at something on the floor by Alex’s lab bench. It’s a long stare, intent and specific.

“And then there were none,” says Zell with a wink.

My eyes on Maxim, I feel something twist and buck inside me. For a moment, his head tilted, his shoulders slightly hunched, Maxim seems about to duck down to look closer. What is it…is that—

Or am I imagining it, all of it?

But then the door opens and Dr. Severin appears and Maxim snaps straight as a pole. We all do.

“They’ll want to ask each of you a few questions. Please cooperate,” Dr. Severin says, tapping her boot on the floor of G-21. “But do it as efficiently as possible. I’d like to have this over before the dean’s dog and pony show.”

She’s wearing her black lace-up boots with crimson insets. Heels that could gore a toreador. Every time her foot hits the floor—so near the spot Maxim’s eyes landed moments before—I think of the red pool, a lagoon now in my head, a swamp, that had been there a few days ago.

Every time her heel hits, I imagine it puncturing the smooth white, and a red fountain spouting from the spot.

“We have a great deal to do to facilitate the transition, reconfigure the lab space for the new study,” she says, looking around the room, the benches crowded with work, with slides and crusted glassware, a rainbow of Post-it notes, pipette tips like star points.

“The detectives are using my office,” she adds. “Fleming’s in there now.”

I look up with a start and see Severin watching me. Now I have to say something.

“But is Alex…,” I say. “Do they think something happened to him?”

Severin lifts an eyebrow.

Was no one going to ask that? I think. I’m the only one who knows and I’m the only one who asks?

“I don’t know what they think,” she says. She moves toward the door, her eyes on me. Everyone’s eyes on me now.

“I’m just concerned,” I say, unable to banish the just. “For Alex. I mean, he was one of us.”

Severin gives me a funny look.

“You mean is,” she says. “He is one of us.”

Diane is in there with the detectives.

I haven’t seen or heard from her since the ladies’ room the day before and, against all logic, I feel a strange tug. The tingle of a missing limb. We share this thing. We share this.

But when I imagine her talking to the police, when I imagine her under the hot lights, I start to feel a dull dread slowly sharpening.

After all, do I have any idea what she would do in the face of police?

Does she know what I would do?

I know what we’re supposed to say. What we’ve been saying: Left at nine, left to do a tour of the town, just a regular welcome wagon, I am. And, yes, we saw Alex. And, yes, walking out, we saw Serge.

Serge. The only person who saw Diane and me at the lab on Saturday. The only witness. What will he say to the detectives? About the biohazard bag, my odd attire, a lab coat subbing as a dress.

Serge has always liked me, I think. Serge would never—

The vivarium is quiet, tomblike as ever.

“Serge?”

I think even just seeing his face, I’ll know if something’s wrong.

As soon as I pass the cage-wash room, I spot him sitting down on one of the benches, his head in his hands.

I hold my breath.

“Serge,” I say. “Are you okay?”

When he looks up, I see it, the great puff of his cheeks, like a cartoon chipmunk’s.

“Oh Jesus,” I say, “does it hurt?”

He shakes his head.

“Can you talk?”

He nods, then whispers, his voice even lower than usual, curiously sultry. “I can, yes. How are you, Kit?”

We are going from cage to cage, looking at the mouse pups, determining which ones are ready to be weaned.

“How old are they?” I ask.

“Nineteen days,” he says, his voice even more muffled now by the masks we’re wearing. “If we wait too long, they may end up mating inappropriately.”

Or, as Zell once put it, they might get plugged by Papa.

“Serge,” I say, “you heard about Alex?”

He nods. “It is unfortunate.”

“It is.”

“But he is a capricious young man, so.”

He can’t suspect anything, I think, or he wouldn’t say that.

“Did you know the police are here?” I ask, trying to play it cool.

Serge nods again. “I have spoken to them.”

I look at him, wanting to pull the mask down, so hot against my face.

“It was very routine,” he says.

Inwardly, I sigh with relief.

“But I waited a long time,” he adds. “I thought they would never be done with her.”

“Done with…her?”

“Diane Fleming.”

I turn my head, adjusting the mask, the loops pinching my ears.

“Oh,” I say. “And she was with them awhile?” He nods. “Did she seem okay? When she came out?”

Serge pauses, standing over one of the cages, thinking.

“I cannot say,” he says. “She would not look at me.”

There it is again. That curious tension when Serge talks about Diane.

“But,” Serge says as we move to the next cage, an even more wrinkly mass of pups, like rosy pearls, “I do not take it personally. Some people are very focused on themselves.”

I look at him, and he looks at me. I can see only his eyes, which seem to be telling me something. Just as, a few days before, he told me about Alex, the political animal. A warning. One that came too late that time.

“Do you see what I mean, Kit?” he adds.

I nod, the mask sucking into my mouth now. Would Diane say something to the police? Would she take that chance, given what she knows I know? And why?

But did I really know what any of her motives were, ever? And she had lied to me about her history with Dr. Severin. Lied by omission.

“These had been fighting,” Serge notes, looking into the cage, “so we removed the dominant one. It will be better, don’t you think?”

I nod thoughtlessly. He guides me to the next cage.

“Did you know,” I whisper, watching Serge place his hands on the cage top, “that Diane worked for Dr. Severin before, years ago?”

“Of course,” he says. “I was there.”

I look up at him, my mouth opening behind the mask. I don’t know what to say.

“The most accurate test for weaning,” Serge says, lifting the lid on the cage, “is this.”

We both look down into the open cage.

Inside, the bitty mouse pups, like pink eraser stubs, do not move at all. Instead, they seem to stare up at us.

“They are not ready,” Serge says, closing the lid firmly.