Six hours, twelve minutes.

I knew the gap between doses the way other people knew their own pulse. I sat in the lab at the back of the clinic, fluorescent light splitting my reflection in the autoclave glass, and laid out the morning kit the way I always did. Suppressant pill in the small white dish. Patch in its sealed pack. A sealed dropper of the eye solution. Three glass vials I had mixed myself last Sunday in this exact light.

The wolf in my chest had been awake for fifty-two minutes. She knew the schedule. She also knew it was failing. We had agreed not to talk about it.

I tipped the pill onto my tongue. Swallowed dry. Counted to ten. Pressed the patch on the inside of my left forearm, low, where a sleeve would cover. Eye drops, one in each, blinked twice, looked up. Silver flickered at the edges of my vision and steadied to gray under the contacts.

Six hours and counting again.

I closed the kit. Locked it back in cabinet three. The key went on the carabiner at my belt with the others, and the others rattled when I moved.

Iris arrived at six, like she did every morning, like she had for nine years. She came in talking. She always came in talking.

"My daughter has decided she wants to be a vet, but only for cats. Specifically the mean ones. I have raised a sociopath." She set two coffees on the steel counter and tossed me mine. "Wren. Tell her cats are bad money."

"Cats are bad money," I said.

"Helpful."

The autoclave ticked. Iris was tying back her hair, one eye on the schedule, narrating her own week to me in a way that did not require my participation. She did this so I could choose to participate or not. She had figured out years ago that I liked the option more than the talking.

"Pete is back at six-thirty," she said. "The shifter dog. New owner. I put him on top because Marcie is doing the cat surgery at seven and I do not want her near a half-shift."

The wolf in my chest moved an inch toward the schedule book.

I made my hand pick up the pen instead and circle Pete's name. "Owner came with him last time?"

"Just a guy in a truck." Iris shrugged, sipping. "Took the dog, paid in cash, said he'd be back."

"Cash."

"Cash, Wren. People still do it. The world is wide."

The wolf settled.

It was a normal morning. Coffee. The autoclave tick. Iris's drugstore vanilla perfume hitting the air with her own scent under it, warm and harmless, the kind of scent I had built my whole adult life around being able to register without flinching. The kind of scent that proved my chemistry was working.

The chemistry was not working.

I had known for two weeks. I had not let myself name it. Twelve years was the ceiling. Halden told me twelve years was the ceiling once when I was nineteen, and I had assumed she was being conservative because chemists were always conservative, and I had mixed batch one hundred and forty-three on Sunday and watched my own hands shake while I measured.

How long can I last on the dose?

The question had been the floor of my mind since I was fifteen. The answer used to be: as long as I keep mixing. The answer was changing.

The truck pulled in at six twenty-eight.

I heard it from the lab. Diesel idle. A working truck, dust on the wheels. The dog whined from the backseat before the door opened. I went out front because Iris was bringing in the second coffee pot.

Pete was on his side in the truck bed when I reached him. Half-shifted. Eyes blown black, paw still partly hand. The smell hit me first: blood, fear, and something I had trained myself to ignore rolling underneath both. Wolf. Real wolf. A pack-marked one.

I put my hand on Pete's flank without looking up. "Hey, sweetheart. Hi. Stay with me."

The owner was at the tailgate. He did not say hello. He said, "What do you need."

I looked up. I had not meant to. I had meant to keep looking at Pete.

He was tall. Lean through the shoulders, broad through the chest, and he held the dog with the kind of quiet that was not for show. Dark hair. A jaw that needed a shave. A plain dark jacket, no logo, no leather. Brown eyes, the flat brown of creek stones, and they were on Pete and not on me.

He smelled like cold water. Like juniper. Like a scent I would not name.

The wolf in my chest knew the word.

I would not let her say it.

"Exam table," I said. "Carry him. He'll bleed less if we keep him level."

He picked Pete up the way a person might pick up a baby. No effort. No wasted movement anywhere. The dog was ninety pounds and did not register on his arms. He waited for me to open the door before he walked through it. He did not crowd me.

He stepped back when I moved toward the supply cabinet. Not a small step. A deliberate one. Six inches, then another six. The kind of distance you would only put between two people if you were thinking about distance.

The wolf in my chest noticed. The wolf in my chest also noticed the inhale he took before he caught it, his chest rising once and stopping mid-breath like he had decided against finishing it.

I went to cabinet four, the sedation cabinet, the safe one. Not three. Not three.

"What's his shift schedule been?" I asked the dog, not the man.

"Two days unstable," he said. "Yesterday he was almost human. He's regressed since this morning."

"Trauma to the abdomen?"

"He took a kick from a horse."

"Idiot horse or idiot dog?"

A small huff of breath behind me. Almost a laugh.

"The horse had reasons," he said.

"They always do."

I drew up the sedation. My hands were steady. They were steady because I had decided they would be. The man stood at the head of the exam table with his hand on the dog's ear and his other hand at his side, fingers slightly curled, and I clocked the slight curl because I clocked everything about him already and was going to have to stop.

"Owner will be okay if I keep him a few hours?" I asked.

"I'm the owner."

I looked up again. I had told myself not to.

"Got him from the previous family last week," he said. "Pete didn't take to me. We're working on it." His mouth did the thing his mouth was going to do for the rest of the book, I could already see it, a small expression that did not show enough of his teeth to be a smile. "I'd like him to live."

"He'll live," I said. "Sit. Or stand. Pick. I need quiet."

He picked still. He stood at the dog's head. He did not move while I worked, and his stillness was not the stillness of a person waiting. It was the stillness of an animal who knew how to wait.

I closed the abdominal wound. A shallow gash, dirty, more bruise than cut. The horse had been kind, considering. I cleaned. I sutured. I taped a butterfly because the dog would worry the larger bandage. The whole thing took twenty minutes. The man stood for twenty minutes without speaking and without shifting his weight.

When I was done, my left contact had fogged. I did not turn away to swap it. I would not let him watch me touch my eye.

"He'll sleep three hours," I said. "I'll keep him in recovery. You can leave or you can stay."

"I'll stay."

"There's a chair in the waiting room."

"I'll stand."

Of course he would stand. I went to the sink. Washed up. The water ran cold over my wrists and I let it run a long time.

When I turned around, he had moved. He was at the door now. Six feet from me again. He had given me the room.

"Do I owe you anything more than the visit fee?" he asked.

"Iris will run the card."

"I pay cash."

"Iris will count the cash."

He nodded.

He did not move to the door. He stood with one hand on the frame, the other at his side, and I had the distinct, unpleasant sensation that he was working very hard not to inhale again. He had inhaled twice since he came in. He was not going to inhale a third time.

"Thank you," he said. "Wren."

The cover name landed in the air between us like a stone in water.

"Welcome," I said.

He left.

I stood in the recovery room with the dog. The dog breathed slowly. I put my hand on the dog's ear because I needed somewhere to put it. I counted his breaths because I needed something to count that wasn't hours.

Iris came in five minutes later. She had her phone out. She did not look at me.

"Just got a text," she said. "Two days running, a black F-three-fifty has been idling on the corner across from us. Plate's not local. I told you yesterday. I'm telling you again."

"Heard you."

"Wren."

"I heard you, Iris."

She did look at me then. She had a face that should have been harder, given the teenager and the rough marriage and twenty years of dead animals. The softness she had kept was a weapon. She used it on me sometimes.

"You're white," she said. "You okay?"

"Long morning."

She left it. She always left it. She would not always leave it.

I went back to the lab. Cabinet three. I unlocked it, took out the kit, looked at the small white dish where the next pill was waiting. The wolf in my chest knew it was four hours and forty minutes early.

The wolf in my chest also knew the man's scent had cut through the patch, the contacts, and the pill in my blood.

I took the pill anyway. Closed the kit. Locked it. Put my forehead against the cabinet door for ten seconds. No more.

How long can I last on the dose?

I did not have an answer that I liked.

Pete shifted in the recovery room, small, twitching paw becoming finger and back, and I went to him because he was easier than the question.

The wolf in my chest stayed awake.

She had not been awake in twelve years.