'Fine,' she said, not bothering to disguise the fact that it wasn't really fine at all. Rebus stood his ground for a moment, as if about to muster some words, then waved the cigarette in her direction and headed for the door.

'And thanks for the lunch,' she said, as soon as he was out of earshot.

Rebus thought he knew why they could barely hold a five-minute conversation without starting to snipe at one another. It was bound to be a tense time, him leaving the field of battle, her on the cusp of promotion. They'd worked together so long – been friends almost as long… Bound to be a tense time.

Everyone assumed that they'd slept together at some point down the line, but no way either of them would have let it happen. How could they have worked as partners afterwards? It would have been all or nothing, and they both loved the job too much to let anything else get in the way. The one thing he'd made her promise was that there'd be no surprise parties his last week at work. Their boss at Gayfield Square had even offered to host something, but Rebus had thanked him with a shake of the head.

'You're the longest-serving officer in CID,' DCI Macrae had persisted.

'Then it's the folk who've put up with me who deserve the medal,'

Rebus had retorted.

The cordon was still in place at the bottom of Raeburn Wynd, but one of the locals ducked beneath the blue-and-white-striped tape, resistant to the idea that anywhere in Edinburgh could be off limits to him. Or so Rebus surmised by the hand gesture the man made when warned by Ray Duff that he was contaminating a crime scene. Duff was shaking his head, more in sorrow than anything else, when Rebus approached.

'Gates reckoned this is where I'd find you,' Rebus said. Duff rolled his eyes.

'And now you're walking all over my locus.'

Rebus answered with a twitch of the mouth. Duff was crouching beside his forensic kit, a toughened red plastic toolbox bought from B amp;Q. Its myriad drawers opened concertina-style, but Duff was in the process of closing them.

'Thought you'd be putting your feet up,' Duff commented.

'No you didn't.'

Duff laughed.'True enough.'

'Any joy?' Rebus asked.

Duff snapped shut the box and lifted it with him as he got to his feet. 'I wandered as far as the top of the lane, checking all the garages along the way. Thing is, if he'd been attacked up there, we'd have traces of blood on the roadway.' He stamped his foot to reinforce the point.

'And?'

“The blood's elsewhere, John.' He gestured for Rebus to follow

and took a left along King's Stables Road. 'See anything?'

Rebus looked hard at the pavement and noticed the trail of splashes. There were intervals between them. The blood had lost most of its colour but was still recognisable. 'How come we didn't spot this last night?'

Duff shrugged. His car was parked kerbside, and he unlocked it long enough to stow his box of tricks.

'How far have you followed it?' Rebus asked.

'I was just about to get started when you arrived.'

'Then let's go.'

They began walking, eyes on the sporadic series of drips. Tou going to join SCRU?' Duff asked.

'Think they'd want me?' SCRU was the Serious Crime Review Unit. It consisted of three retired detectives, whose job was to look at unsolveds.

'Did you hear about that result we got last week?' Duff said.

'DNA from a sweated fingerprint. Sort of thing that can be useful on cold cases. DNA boost means we can decipher DNA multiples.'

'Shame I can't decipher what you're saying.'

Duff chuckled. 'World's changing, John. Faster than most of us can keep up with.'

'You're saying I should embrace the scrapheap?'

Duff just shrugged. They'd covered a hundred yards or so and were standing at the exit to a multistorey car park. There were two barriers; drivers could choose either one. Once you'd paid for your ticket, you slid it into a slot and the barrier would rise.

'Have you ID'd the victim?' Duff asked, looking around as he tried to pick up the trail again.

'A Russian poet.'

'Did he drive a car?'

'He couldn't change his own lightbulbs, Ray.'

'Thing about car parks, John… there's always a bit of oil left lying around.'

Rebus had noticed that there were intercoms fixed alongside either barrier. He pressed a button and waited. After a few moments, a voice crackled from the loudspeaker.

What is it?'

'Wonder if you can help me…'

“You after directions or something? Look, chief, this is a car park.

All we do here is park cars.' It took Rebus only a second to work things out.

Tou can see me,' he said. Yes: a CCTV camera high up in one

corner, pointing at the exit. Rebus gave it a wave.

'Have you got a problem with your car?' the voice was asking.

'I'm a cop,' Rebus answered. 'Want to have a word with you.'

'What about?'

'Where are you?'

'Next floor up,' the voice admitted eventually. 'Is this to do with that prang I had?'

'That depends – did you happen to hit a guy and kill him?'

'Christ, no.'

'Might be okay then. We'll be there in a minute.' Rebus moved away from the barrier towards where Ray Duff was down on all fours, peering beneath a parked BMW.

'Not keen on these new Beamers,' Duff said, sensing Rebus behind him.

'Found something?'

'I think there's blood under here… quite a bit of it. If you were asking me, I'd say this is trail's end.'

Rebus walked around the vehicle. There was a ticket on the dashboard, showing that it had entered the car park at eleven that morning.

'Next car along,' Duff was saying, 'is there something underneath it?'

Rebus did a circuit of the big Lexus but couldn't see anything.

Nothing else for it but to get down on hands and knees himself. A bit of string or wire. He reached a hand beneath the car, fingertips scrabbling at it, eventually drawing it out. Hauled himself back to his feet and held it dangling by thumb and forefinger.

A plain silver neck-chain.

'Ray,' he said, 'better go fetch your kit.'

Clarke decided it wasn't worth visiting the librarian, so called her from Todorov's flat while Hawes and Tibbet started the search.

Clarke had barely punched in the number for the Poetry Library when Hawes arrived back from the bedroom, waving the dead man's passport.

'Under a corner of the mattress,' Hawes said. 'First place I looked.'

Clarke just nodded, and moved into the hallway for a bit more privacy.

'Miss Thomas?' she said into her phone. 'It's Detective Sergeant Clarke here, sorry to trouble you again so soon…'

Three minutes later she was back in the living room with just a couple of names: yes, Abigail Thomas had accompanied Todorov to the pub after his recital, but she'd only stayed for the one, and knew that the poet wouldn't be satisfied until he'd sampled another four or five watering-holes.

'I reckoned he was in safe hands with Mr Riordan,' she'd told Clarke.

'The sound engineer?'

Tes.'

'No one else was there? None of the other poets?'

'Just the three of us, and as I say, I didn't stay long…'

Colin Tibbet meantime had finished rummaging through desk drawers and kitchen cupboards and was tilting the sofa to see if anything other than dust might be hidden there. Clarke lifted a book from the floor. It was another copy ofAstapovo Blues. She'd managed a couple of minutes' research on Count Tolstoy, so knew that he'd died in a railway siding, shunning the wife who

had refused to join his pared-to-the-bone lifestyle. This helped her make more sense of the collection's final poem, 'Codex Coda', with its refrain of 'a cold, cleansed death'. Todorov, she saw, had not quite finished with any of the poems in the book – there were pencilled amendments throughout. She reached into his waste-bin and uncrumpled one of the discarded sheets.