The Karrow Medical Examiner worked out of a former customs house on the south quay, a squat sandstone building with a clock that had stopped at twenty to four and a brass plate that had been polished so often the words had half worn away. Imani got there at ten past eight on Thursday morning, damp from the ferry, with the freezer bag in her inside pocket and four hours' sleep behind her eyes. The reception desk was staffed by a young man in a cardigan who looked up from a screen showing a game of cards and said, "Do you have an appointment with the dead?"

"With Mr. Nakagawa."

"Same thing, mostly. Second floor. Mind the third step, it bites."

The third step did bite. It was loose, and it rang in the stairwell like a wrong note. At the top there was a corridor of pale green doors, a vending machine selling soup, and a door at the end that stood ajar, from which came the smell of burnt coffee and the sound of a man eating cold pizza very quietly.

Idris Nakagawa was at a desk piled with files, a laptop open at his elbow and a slice in his hand. He saw her in the doorway and got to his feet at once, took the pizza in both hands, found nowhere to put it, and finally set it on top of a folder labelled DROWNINGS (HARBOUR) in a gesture that appeared to cost him real pain.

"Miss Quaye."

"Mr. Nakagawa."

"I didn't expect you so early. Did you eat?"

"I had the ferry."

"A ferry is not food." He pushed his glasses up the bridge of his nose. The paperclip on the hinge had been replaced by a small neat blob of what looked like surgical tape. "There's a banana. It's mine. I haven't touched it." He held it out, formally, as one might offer a witness a document.

She took it. It seemed less rude than not to. "Are you always like this?"

"Like what?"

"Never mind." She peeled the banana, and sat, and he sat, and for a moment they looked at each other across a desk covered in other people's last days. In daylight he looked younger than she had thought, perhaps thirty-five, with a long serious face that did nothing it hadn't been asked to. There were shadows under his eyes. He had cut himself shaving and put a small square of tissue on it, and forgotten.

She laid the freezer bag between them.

"This is from the soil lift," she said. "A wooden service hoist on the east side of the tower. It goes from the basement to the roof, and it has never been wired to the lift system. I think it's how the body came in. I found these on the floor. There was a lot of them, in the cracks. The car had been scrubbed with lemon cleaner but whoever did it missed the corners."

Idris looked at the bag. He did not pick it up.

"Where did you get access to the soil lift?"

"I had a key."

"Whose?"

"My father's."

"Is it lawful for you to have it?"

"It's mine by inheritance, if anyone's." She held his eye. "Is that a problem?"

"I'm not a police officer," said Idris. "I'm an investigator for the Medical Examiner. I can't arrest you or search you. I do have to put in my report where I received any item of evidence, and I would like to be able to say that it was given to me freely and honestly by a member of the public, and that I did not require you to lie." He paused. "If I ask you a question and you decline to answer, I'll write that you declined. I won't write anything else. I find the alternative difficult. I'm sorry; I'm not good at the other sort."

"The other sort?"

"Of report. The kind where people say things that are almost what happened."

She thought about that. Then she said, "There's something I'm leaving out."

"Thank you," said Idris.

"That's all?"

"It's a great deal. Most people say they aren't." He picked up the bag by one corner and held it to the window. The hairs inside were tiny and black and grey; they might have been pepper. "A beard," he said. "Trimmed, not shaved. Cut with scissors or clippers, by someone in a hurry. Hair this coarse and this dark would be consistent with a man of about forty with a full beard. May I take it?"

"That's why I brought it."

"I'll send it for a DNA comparison. Against what?"

"I don't know. Piet Lindqvist's toothbrush?"

"That would be an excellent start, if anyone had it." He put the bag in a clear evidence pouch and wrote on it with a fountain pen, in an upright, careful hand, and then did something she did not expect: he pushed his laptop across the desk, turned it round, and said, "I want to show you something. I'm not sure I'm allowed to."

"Then why are you?"

"Because I haven't been told I'm not." He tapped a key. A scan came up: black and white, grainy, a pair of dental X-rays laid side by side like a pair of shy hands. "The tower's insurer sent me Mr. Lindqvist's dental records yesterday afternoon, as I asked. Panoramic film, bitewings, a treatment history. They match the body. Every filling, the crowned molar on the lower left, the missing wisdom tooth. It is a very good match. That is the first thing."

"The second thing is you don't like it."

"The second thing," said Idris slowly, "is the file." He clicked on a tab. A string of small grey text. "Every file carries metadata. It's a record that a computer makes about what it is, who made it, and when. This file says it was created at eight-oh-two yesterday morning. The body was found at seven twenty-four. Mr. Lindqvist's dental X-rays were supposedly taken three years ago, during a routine check-up, and this is a clean digital export from the insurer's portal. But the portal says the account was *accessed* from a terminal on the thirty-first floor of Ostrander Tower, thirty-eight minutes after you opened the lift."

Imani stopped with the banana halfway to her mouth.

"They uploaded his records," she said, "to the insurer."

"Or they uploaded a record to the insurer, and the insurer then sent it to me as though it were their own." He rubbed his eyes under the glasses. "It may be nothing. It may mean Security opened the account for a legitimate reason, to help me. People do that. They try to be useful." The corner of his mouth moved. "I don't think so, though. I think someone wanted me to have a match by lunchtime."

"A match to Piet."

"A match to *a* man. I don't yet know whose teeth they are."

The vending machine in the corridor shuddered and dropped something with a clunk. Imani put the banana down. Her hands, she noticed, were slightly unsteady. She found that she did not mind him seeing.

"Mr. Nakagawa."

"Idris. Please. If you're going to shout at me I'd prefer to be shouted at by first name."

"I wasn't going to shout."

"No. You seem like someone who would say it very calmly and then I would feel as though I'd been shot." He said it with a straight face. She looked at him. He looked at her, perfectly serious, and she could not tell, for several seconds, whether it was a joke, and then realised with a little jolt that it was one, and had been all along.

"Idris," she said. "If the dental record is false, then the body isn't Piet. Which would make me right. Or it's a different dead man altogether."

"Or the record is true and merely placed there in a hurry by a security chief who wanted to be helpful. That's the other reading." He was already typing. "I won't know until I speak to Mr. Lindqvist's own dentist. He's registered with a practice in Dunmore. I rang them yesterday. They said the records had been *requested* and that a senior colleague would be in touch."

"Who requested them?"

"The call log doesn't say. But the call came from a number with a Karrow exchange." He turned the laptop. "I've been awake since yesterday morning, Miss Quaye. I'd like to tell you I've made progress. In fact I've made a list of ways that I might be wrong, and I find it increasingly interesting."

He didn't smile. His eyes did. She had not known that was possible.

Then the door opened with a bang.

The young man from reception stood there in his cardigan, his face the colour of milk, holding a printed sheet of paper in both hands as though it were hot.

"Mr. Nakagawa," he said. "Sorry. This came in by courier. It's from the Coroner's office. Director Abelard-Singh's lawyers. They want the body released."

Idris took the paper. He read it. She watched him read it, the careful eyes going down the page and coming back up, and then he read it again from the top.

"On what grounds?"

"It says the tower's family has requested release of the remains to their own funeral directors under the Private Estate Incident Protocol," the young man said. "Because he's staff. It's a kindness. The undertakers are coming at noon."

"It's a protocol I've never heard of."

"I looked it up. It's real. It's from 1998. Nobody's ever used it."

"No," said Idris Nakagawa. He laid the page on the desk very gently, as if it might bruise, and said to nobody in particular, in the voice of a man reading out a sentence in a language he disliked, "They're going to take him out of the building before I can find out who he is."

Imani looked at the clock above the door. It said twenty past eight, and had not stopped.