Tilney's eyes were wandering around the cluttered room. 'He would have been wearing a seat-belt, and therefore wasn't thrown clear, and the fire started so fast that you didn't have a chance of reaching him in time. Wasn't that it?'

'I should have -'

There was nothing you could have done, obviously.' He was watching me again now.

'I should have been ready for it.'

Tilney looked down, folding his pale hands on the desk beside the tape-recorder. 'It's going on record that in my opinion and from what you've described, there was quite clearly nothing you could have done to help McCane last night.'

I left it. The other car,' I said, 'kept on going. They hit the brakes once – I was waiting for them to turn and come back and make sure they'd done the job, but when they saw the tank go up they must have known he hadn't got a chance.'

'What kind of car did they have?'

'A dark Mercedes. I didn't see much of it – I was watching McCane's.'

'Of course. Then you phoned Signals?'

'Yes. I told them to pass it on to whoever was running him. I didn't know it was Shatner.'

'Did anyone -' he stopped, tilting his head; there'd been the slam of a door. He picked up the intercom phone and I waited, my body heavy in the worn leather chair, my eyes wanting to close. But I wasn't going to catch up on my sleep until I'd seen Shatner.

There was only one thing, really, I could do that would get me at least some of the way out of this appalling sense of guilt, almost of betrayal, and Shatner could help me do it. But I'd have to be very careful.