This is how she tells it.

It was more than eight years ago, before she had this lab, her own lab, when she was still climbing hard, knuckles pressed against rock.

She was recruiting participants for a new intramural study on possible genetic factors and PMDD. All day long, her grad students interviewed potential subjects, mostly undergrads drawn in by flyers posted across campus promising UP TO $800 for taking part in the diagnostic testing and interviews. Students were so easy. They’d come just for wax-cup coffee and orange Milanos. And it seemed nearly every college girl who’d ever read Sylvia Plath, which was nearly all of them, longed to be told she suffered from PMDD.

She sometimes watched the interviews through the one-way mirror like a police inspector on a television show. None of the students ever seemed to notice as they nibbled on their cookies, or pretended to. Talking about their bodies and their blood. Their feelings and the heat of them. They were all the same, with their oversize sweatshirts and downy cheeks. Their uptalk and their justs and their I guess, I mean, maybe and their equivocations (I don’t know, maybe it’s just normal to feel this way? To cry all the time for days and days and eat and eat until I’m maybe just gonna die from it?).

Eased into comfort by the female grad students in their crisp shirts and stylish eyewear, the cool and measured tones she’d trained them to use when interviewing, the undergraduates opened up like loose-hinged clams. (Ice the muscle first, her father used to tell her on summer trips to Mustang Island, and they’ll pop like a prom date.)

But Diane was different. She came on the last day. Everything about her was reserved, even the way she held the proffered cookie, fingers barely touching its edges, like it was a foreign object. She never took a bite, never drank any of the coffee or aromatic tea. Back straight, her head high, her voice low, deep, thoughtful, she spoke clearly, sparingly. She never shifted in her chair, twirled her hair, or tugged her sleeves over her hands like all the others did, girlish and coy. She never spoke in anything other than a low purr.

Yes, anxiety. Tension? Yes. Mood changes? Yes, those too. Yes, hostility. Hostility and other feelings as well.

Because there was a music to it, like a hypnotist’s voice. Or like someone who spent most of her time talking to herself, talking in her own head.

Urges that I can’t seem to manage. Often, I have this feeling of…disorder inside.

When she spoke, she faced not the graduate student interviewing her but the mirror behind. The only one of dozens those first few days who understood what it was all about.

But, after all the tests and interviews and forms, Diane didn’t meet the diagnostic criteria for PMDD and so her name did not appear on the list of chosen subjects posted outside Dr. Severin’s door.

But I need help, she insisted to the departmental secretary, her fists clenched at her sides. I must be chosen. I need to be chosen.

Watching from her office door, Dr. Severin, for reasons still murky to herself, ended up inviting Diane inside. She said she was sorry but there was nothing that could be done. Diane’s symptoms did not align with her menstrual cycle.

Simply put, she said, there’s no evidence of a connection between your blood and your feelings.

But there is, Diane kept insisting, her voice never wavering. There absolutely is. You’re wrong about me. Everyone’s wrong about me. I have it.

It has me.

Dr. Severin listened to her, overcome by a wave of feeling. This is someone, she thought, who has learned something very troubling about herself and does not know what to do.

That evening, the experience kept humming in her head. The name, it was familiar. Diane Fleming.

It wasn’t until she, somewhat unethically, looked up Diane’s student record that she began to put it together. Diane had graduated from one of the high schools in her scholarship pool.

Had she applied? Indeed she had.

She turned to her scholarship files and found it. That odd letter forwarded to her by the committee chair two years ago. The confidential missive from some guidance counselor at one of those chem-chugging, dying towns by the state line.

It pains me to have to tell the scholarship committee members this. A student has come forward with some upsetting information about Diane Fleming. I cannot confirm the details, but I find this student to be very trustworthy. I do believe her. I realize that the scholarship awards are based on academic excellence but a key guideline is the “integrity and ethical values” of the applicant and these areas are very much in doubt.

Attached was the obituary. Diane’s father. That brush of a mustache and gloomy expression. Medical examiners in those parts don’t have elaborate equipment. No mass spectrometer, which could run you a hundred grand. But they do have assumptions, and they assumed. If no family member asks, they assume. Cardiac failure. His heart stopped. Sad, really.

Her first thought had been: Skip it. Who knows if it’s even true? This could be the poison-pen letter of a jealous competitor. Maybe even the other scholarship finalist.

But her committee chair seemed concerned. We can’t afford to cast a pall over our women-in-sciences scholarship. Our mission is too important.

And so no one had done anything. And no one told anyone either.

It’s not our business, she’d thought.

But now, having seen Diane Fleming, she supposed it might be true. Something was consuming the girl. I need help.

She thought of her in that interview room, slightly breathless and entrancing. Wanting desperately to be told that nothing was her fault, that her body and brain had conspired against her. The feeling she must have, always, of being in between worlds, the worlds separated only by an impenetrable pane of glass.

It wasn’t until two years later that her name came up again, in a stack of applications for summer internships in the Severin Lab. With an appointment to lecture in Grenoble, she knew she wouldn’t be there, but she didn’t hesitate to give the slot to Diane. She had all the bona fides and Dr. Severin couldn’t help but feel sorry for her in some quiet way. She too understood something about the ways people—women—had to isolate themselves to protect themselves. To keep going.

It turned out, however, that there was some trouble in the lab in her absence. Diane hadn’t really fit in and hadn’t participated in any of the group extracurriculars. And then there was the matter that had to be addressed: the incident report one of the junior lab techs had filed about her treatment of the animals.

“Serge,” I say. “That was Serge.”

“He couldn’t let it go. That’s why he was the best.”

I look at her.

“Poor Serge.” She shakes her head. “He was always burdened by a kind of male rigidity. Black and white, right and wrong. It’s harder for men to understand. Some men.”

I nod, putting my cigarette out.

“Women have to live so much of their life in the in-betweens.”

Serge’s incident report was faintly hysterical, but it was Dr. Severin’s duty to follow up. She hoped she might talk seriously with Diane. Encourage her to get some kind of treatment. And, if Diane was resistant, perhaps move the report forward to the dean.

But when she arrived at the lab and saw Diane—that soft golden leaf of hair, the delicately blinking eyes, the steady hands as she held the test tube up to the light, studying it—Dr. Severin found herself inexplicably moved.

The girl, she thought, has no one in the world looking out for her.

So she took her to dinner. Diane had a late train that would take her far away, to graduate school on the opposite coast, and so they sat at the station diner and drank coffee and ate hot turkey sandwiches and talked about the work Diane would be doing next, studying gender differences in parent-child bonding, injecting oxytocin into the brains of voles.

Finally, as she was paying the check, Dr. Severin decided to ask. Had she ever gotten help for the things she’d been feeling two years ago? The disordered thoughts?

Diane smiled faintly and said yes.

Leaning forward, she confided she’d had that all taken care of.

Taken care of?

It’s all gone.

Gone.

And she confided that she’d had a radical hysterectomy, elective.

The keyhole surgery, she said. I used an inheritance and had it all taken out.

Just shy of eleven o’clock, they stepped out onto the dusty train platform. Staring up at the sky, Diane said it reminded her of the first time she ever saw micrographs of astrocytes, those exquisite star-shaped brain cells, and discovered the strange beauty of science.

It was astonishing to me to think the human brain has more cells than there are stars in the Milky Way.

But as they waited, spotting the train’s smoke swirl in the distance, all Dr. Severin could think of was this girl, this young woman, had chosen to have her womb cut from her body for no reason at all. Or, at least, no reason that made any sense.

Untimely ripped—the phrase came to her.

The train approaching, whistles and horns screaming, Dr. Severin found herself moving toward her to hear, closer and closer until their faces were inches apart.

You know I saw you once, Diane said, grabbing for her bags. I was just a high-school student, fifteen, she said, but you talked to us about women and science. You were showing these brain scans and I knew what I wanted to do, to be. The blood is the life, you said.

As the train thundered in, enveloping them both in the manner of a Russian novel, she found herself placing her hand on Diane’s gleaming forehead.

Show them what you’ve got, she said, show them what you have in there.

She wasn’t even sure what it meant.

As Diane stepped onto the train, Dr. Severin was thinking that the brain was a monstrous and beautiful thing. A ravishing chaos.

Shouting over the chugging train, the brake pipe and conductor’s cry, the crackling intercom, Dr. Severin reached for her arm, thin as kindling.

Dr. Severin, do you remember the first time you held one in your hands? A brain?

Yes, Dr. Severin said. Of course.

How did it make you feel?

Humbled, she said honestly.

A quizzical look came over the girl’s face.

Really? Diane replied, just as the train began pulling away. It made me feel powerful.

“Last year, in the hiring pool, her name came up, and then came up again. A rising star,” Dr. Severin says to me. “I don’t know. Call it curiosity, call it something else, something…”

She cleared her throat, hiding her eyes from me.

I don’t say anything, still thinking of Diane, her womb plucked out. Her shorn hair and shorn body. The wormy logic of her wormy brain.

“It’s best,” she says, “to think of Diane as a sick person like any other kind of sick person. She can’t help what she is.”

What she is. But what was she before?

Or did I already know?

I think about her that first time at camp, before everything with her dad, before her exile at her mother’s hands. In the hotel room, how sick she got after all our secrets were told, everyone’s but hers, and how I held that hair in my hand, like a fistful of silk, and the way, sleeping in our shared room’s bed, our bodies curled, the only time we were ever so close, front of knee to back of knee.

I could feel all her breaths, hoarse and high. I could feel her breaths vibrating through me and not even be sure if they were hers or mine.

My mom always says, you don’t have a self until you have a secret.

That girl, that girl. Hurt already a thousand times by fifteen.

“There is something especially hard about mad people who know they are mad,” Dr. Severin says, tapping out her cigarette. “If Diane weren’t so brilliant, maybe she wouldn’t know how mad she is. But she does. And I think that must be a terrible feeling.”

I take another cigarette. “Sorry,” I say, trying to still my shaking hand. “I’m not going to feel sorry for her.”

“Well, Kit,” she says, leaning back in her chair, those legs displayed, one shoe slipping off, “that’s a shame. But, like I said, you’re still so young.”

I drop my head and take a breath, not wanting her to see me.

When I lift my head again, her eyes have gone glassy.

They’re nearly ready for us.

I have no idea what to expect. Obstruction of justice, at best, and what about the lab? The scandal?

We stand and Dr. Severin smooths her hair, then mine.

“You might think about what draws the three of us together,” she says, gathering herself now. “We’ve all tasted the apple, haven’t we? We ate it whole.”

As I walk by, I see her seated on one of the rolling chairs in the animal-prep room, the officer with the mustache standing beside her.

“Are they taking me now?” she is saying, looking up at him. “I explained what I did. I explained about Serge and about Alex and about Dad.”

I wonder if she can see me.

“We need to wait here a minute,” the officer is saying. “Then we’re taking you to the station.”

Her head lifts, golden under the lights, that Saint Joan face, composed and sure.

“I killed them,” she says, eyes skittering toward me. “I killed all of them.”

Detective Harper and her partner, the rooster-breasted one, are waiting for me.

“You don’t have to be afraid of her any longer,” he says. “We got it all in writing.”

“Afraid?”

“She told us how she threatened you.”

I don’t say anything, trying to imagine what she might have said. Alex and I were fighting. He knew my secret. The glass broke. Kit came in after. She wanted to call 911—I pressured Kit and threatened her into concealing everything.

Oh, Diane, I think. I never asked you to do that. I never would.

Detective Harper tells me he’d be very surprised if the DA bothered with me at all. “You were dealing with a multiple murderer, after all,” she says.

“Right.”

“Some days,” her partner says, handing me some forms, “fortune smiles on you.”

“I’ve always been a lucky girl,” I say.

“Or smart enough to make her own luck,” says Detective Harper, looking at me.

I see her from a distance.

The two policemen from before are escorting her back through the vivarium to the door. Her back is hunched, head ducked, and she looks so very small.

I start moving toward her.

“Diane,” I say, unable to stop myself. “Diane, you didn’t have to.”

I can hear Dr. Severin behind me, asking the mustachioed officer if we can approach.

“Diane,” I say, but she doesn’t see me, or won’t look at me.

Her arms drop to her sides stiffly as the three of them pass a long lab bench, stainless steel so bright it hurts my eyes, all the gleaming containers of pipettes, scalpels, specimen scissors and knives, capillary tubes, glass septums.

“Diane,” I say again. “I’m sorry.”

And all I mean is I’m sorry you’re like this. I’m sorry your parents didn’t love you enough and I’m sorry no one ever taught you how to be. I’m sorry for all the feelings you had that you never learned how to stop and most of all I’m sorry your brain couldn’t work out how to live in this world.

But she won’t look at me, and there’s that strange, stilted way she’s walking now, one arm hanging in front of her like a broken limb, her sleeve covering her hand.

“Officer,” Detective Harper is calling out, “can you escort Dr. Fleming to the squad car?”

Diane raises her head and looks at me, at Dr. Severin, both of us still. The feeling inside of something—

“Kit,” she says. “Kit. I fixed it.”

Diane’s long arm lifts, her hand like a white spider. I see the flash of a specimen knife slipping from her sleeve into her palm.

“Don’t, don’t!” I shout to anyone at all.

The officer moves quickly, his arms flying up, but Diane is faster than anyone when she wants to be. Because she’s already so far ahead before you even begin.

“Diane, no!” Dr. Severin cries out.

Her eyes on me, her face trembling, she throws her head back, that long neck bare and gleaming—

The carotid, you die much faster, she’d said. So fast.

—and with one endless sweep she drags the blade forward and across, ear to neck, everything going red.

Her legs falling beneath her, that great burst of blood, bright red, redder than anything I’ve ever seen.

My mouth opening, I’m running forward, a sprinter always, and never fast enough.