Rebus glanced at his watch. A little over ten minutes left . . . She seemed to understand.

‘So, anyway, I asked him if he had a name. And he laughed. He said, “You mean you don’t recognize the face?” I shook my head, and he said, “Of course, you’re a Londoner, aren’t you? Well hen,” he said, “I’m weel kent up here.” Something stupid like that. Then he says, “I’m Gregor Jack.” Well, I just started laughing, don’t ask me why. He did ask me why. So I said, “No you’re not. I know Gregor Jack.” That seemed to put him off his stroke. In the end, he buggered off back to his pals. All the usual winks and slaps on the back, and I didn’t say anything . . .’

‘What did he look like?’

‘Big. Like a Highlander. One of the other girls said she thought she had seen him on the telly . . .’

Rab Kinnoul. Rebus described him briefly.

‘Sounds about right,’ she conceded.

‘What about the men who were with him?’

‘Didn’t pay much attention. One of them was the shy type, tall and skinny like a beanpole. The other was fat and had on a leather jacket.’

‘You didn’t catch their names?’

‘No.’

Well, it didn’t matter. Rebus would bet she could pick them out from a line-up. Ronald Steele and Barney Byars. A night out on the town. Byars, Steele, and Rab Kinnoul. A curious little assembly, and another incendiary he could toss in Steele’s direction.

‘Finish your drink, Gail,’ he said. ‘Then let’s get you on to that train.’

But on the way, he extracted an address from her, the same one she had given before, the one he’d had George Flight check on.

‘That’s where I’ll be,’ she said. She took a final look around her. The train was idling, filling with people. Rebus lifted her suitcase in through one of the doors. She was still staring up at the glass roof of the station. Then she lowered her gaze to Rebus. ‘I should never have left London, should I? Maybe nothing would have happened if I’d stayed where I was.’

Rebus tilted his head slightly. ‘You’re not to blame, Gail.’ But all the same, he couldn’t help feeling that she had a point. If she’d stayed away from Edinburgh, if she hadn’t come out with that “I know Gregor Jack” . . . who could say? She stepped up on to the train, then turned back towards him.

‘If you see Gregor . . .’ she began. But there wasn’t anything else. She shrugged and turned away, carrying her case and her bags with her. Rebus, never one for emotional farewells where prostitutes were concerned, turned briskly on his heels and headed back towards his car.

‘You’ve what?’

‘I’ve let him go.’

‘You’ve let Steele go?’ Rebus couldn’t believe it. He paced what there was of Lauderdale’s floor. ‘Why?’

Now Lauderdale smiled coldly. ‘What was the charge, John? Be realistic, for Christ’s sake.’