‘Conspiracy is right. The Americans and the British are in on it for a start. But the governments don’t seem to know, only the generals.’

The door opened and a well-dressed man came into the café. Hepton glanced up at him, but was too intent on his story to pay him much attention. The man slid into the booth next to theirs, so that his back was to Izzard’s back. Alfie was still in the kitchen, his frying pan sizzling.

‘Only the generals,’ Izzard repeated. ‘So whatever’s happening, what can we do about it?’

‘I really don’t know. We could persuade Whitehall that something’s going on, but the suits in Curzon Street didn’t seem to think it would produce much joy. What we need is proof, absolute proof.’

‘Well, you’ve got that, haven’t you? I mean, the tapes?’

‘But what do they prove? Not what’s happening, only that something is.’

‘So go to Buchan. Take a look for yourself.’

‘Yes,’ said Hepton. ‘Yes, maybe you’re right.’

The newcomer swivelled on his bench so that he was facing their booth. Hepton glared at him, realising that he had heard every word. The man looked pale, tired. Not a killer, not just at the moment.

‘Mr Izzard generally is right,’ he said.

Izzard’s head cracked round at the sound of the voice. Then his face broke into a grin.

‘Why don’t you join us?’ he said. The man got up and did so. Izzard was still grinning. ‘Once,’ he said to Hepton, ‘I went to lunch and came back to the lab, and I’d been in there ten minutes before I realised this sneaky sod was in there too. Just sitting, out of my line of vision, and absolutely still. A professional voyeur, that’s what you are.’

The man took the remark as a compliment. He was holding out a hand to Hepton, who was wondering now where he had heard his voice before.

‘Parfit,’ the man said by way of introduction. ‘We’ve spoken on the telephone. You must be Martin Hepton. They told me you’d come to see Izzard. And since Graeme spends more time in this establishment than in his lab, I thought I’d try here first.’

Hepton shook the proffered hand, a look of disbelief on his face.

‘Parfit?’ he said. ‘Christ, when did you get back?’

‘A couple of hours ago.’

‘Is Dreyfuss with you?’

‘Well, the safe house didn’t appear to be safe any longer, so I’ve booked us into a hotel. He’s resting there.’

‘Does he know …?’