There was no one inside, and the alarm hadn’t been set. He switched on the lights. The loose rug underfoot seemed to want to wrap itself around his ankles, and he had to fight his way loose, holding on to the wall. The rooms were just as he’d left them, except that the computer was now missing from its desk, having been transferred to the station, where Siobhan was certain someone from Balfour’s Internet service provider could help bypass the password.

In the bedroom, someone had removed the neat pile of David Costello’s clothes from the chair. Rebus presumed the culprit to be Costello himself. He wouldn’t have done so without permission – nothing left the flat unless okayed by the bosses. Forensics would have checked the clothes first, maybe taken samples from them. Already there were rumours of belt-tightening. A case like this, the cost could spiral skywards like smoke.

In the kitchen, Rebus poured himself a big glass of water and went through to sit in the drawing room, pretty much where David Costello had sat. A little of the water dribbled down his chin. The paintings on the walls – framed abstracts – were playing tricks, moving with him as he moved his eyes. He bent down to place the empty glass on the floor, and ended up on his hands and knees. Some bastard had spiked the drinks, only explanation. He turned and sat down, closed his eyes for a moment. MisPers: sometimes you worried in vain; they either turned up, or didn’t want to be found. So many of them … photos and descriptions were always passing through the office, the faces slightly out of focus as though they were in the process of becoming ghosts. He blinked open his eyes and raised them to the ceiling, with its ornate cornicing. Big flats, the New Town had, but Rebus preferred it where he lived: more shops, not quite so smug …

The Ardbeg, it had to’ve been spiked. He probably wouldn’t drink it again. It would come with its own ghost. He wondered what had happened to the boy: had it been accident or design? The boy would be a parent himself these days, maybe even a grandparent. Did he still dream about the sister he’d killed? Did he remember the young, nervous uniform standing behind the reception desk? Rebus ran his hands over the floor. It was bare wood, sanded and sealed. They hadn’t taken the boards up, not yet. He felt for a gap between two planks and dug his nails in, but couldn’t get any purchase. Somehow he knocked the glass and it started rolling, the noise filling the room. Rebus watched it until it stopped in the doorway, progress blocked by a pair of feet.

‘What in the hell’s going on?’