The corners of his mouth twitched. ‘Well, you certainly seemed worried about the possibility. I must say I wasn’t expecting you to kill poor old Chief. That’s made life rather tricky for us, I think.’

‘I had to,’ I said, then stopped. I wasn’t going to justify myself to Pritchard. ‘So . . . Slavin was a genuine defector.’

Pritchard shook his head slowly from side to side.

‘But why would Moscow want to expose a long-running double agent?’ I asked. ‘Possibly even two.’

‘Moscow’s a large city,’ he said. My skin was prickling, but I didn’t yet know why. ‘Whom do we work for?’ said Pritchard, and his pale blue eyes searched my face for a reaction. I realized that although he knew it was the end of the road, he was enjoying revealing the plot to me, like a conjuror finally able to show his audience how clever he had been. ‘It’s a simple enough question,’ he said. ‘Whom do we work for?’

‘The KGB,’ I replied, and winced; it sounded so childish suddenly, so cops and robbers.

‘No, Paul,’ said Pritchard. ‘We don’t. When Anna recruited me, it was into Glavnoe Razvedyvatel’noe Upravlenie: military intelligence. She had been persuaded of my good intentions by another of her agents - your father.’

He was lying. He had to be lying.

I knew he wasn’t lying.

A dozen images flew through my head, but above them all I could see my father’s body sprawled across the bed at the farmhouse, one half of his head a ruin.

‘Did you . . .’ My mouth was sewn up. ‘Did you kill him?’

‘But it was I who persuaded Anna to recruit you,’ Pritchard went on, as though I hadn’t spoken. ‘Larry hated the idea - he felt you were too young. He always said that successful recruitment depended on the subject having a firm ideology. I thought you were at precisely the right age to foster that. I proposed we give you the ideology - through Anna.’

It was like listening to some macabre joke. The man whose views he was blithely referring to was unrecognizable to me - and yet, recognizable, too.

‘Larry still wasn’t satisfied,’ said Pritchard. ‘He desperately didn’t want you spoiled by betrayal, as he felt he had been. He didn’t want that life for you. In the end, he had no choice, though: Moscow demanded it. And Larry always obeyed Moscow. I never left for Gaggenau, of course - I was with Anna then. We knew it was only a matter of time before you were injured in one way or other. That cut you got wasn’t much more than a scratch, really. Anna made certain you were isolated, and took care of your treatment. And you walked right into it, of course. Who wouldn’t? She was young, beautiful, good in bed . . .’