‘There’s going to be an attack. Here in London.’ His words were rushed, urgent. ‘Soon. But I don’t know when. The Americans scrambled my head. Everything’s upside down and turned around, and I need you to straighten it out again.’

‘An attack on who?’ Knox asked.

‘I-I’m not sure,’ Williams said, the urgency in his voice turning into anger. ‘But you have to believe me.’

Every fibre of Knox’s being wanted to. Even with no evidence, even with the state of him, Knox wanted to believe Williams.

‘Alright,’ he said, making his voice as soft as possible. ‘What can I do?’

Williams sighed and turned away, his fingers finally slackening their grip as he looked along the Broad Walk towards Parliament Hill in the distance.

‘I need to rest. I don’t know how long it’s been since I slept. I can feel myself breaking apart.’

Knox glanced at Bennett across the road. He could tell she’d noticed Williams’s outburst, and guessed they only had a few more moments together before she’d come back and say their time was up.

Then Knox saw the red roof of a double-decker turning into the far end of Ulster Terrace and realised he actually had mere seconds to decide what was going to happen next.

Should he leave Williams to the fate the CIA wanted, paraded through Whitehall and then disappeared off to be put through more hell? Or should he betray Bennett and help the friend to whom he owed a debt he never thought he’d be able to repay?

There was no choice. He was going to save Williams.

‘Do you remember Geoffrey Pyke?’ he asked.

Williams’s face went blank for a moment, but then he nodded.

‘Good,’ Knox said. ‘Follow me.’

He got up and started to walk towards the gate. As he heard Williams’s feet start to crunch on the gravel behind him he signalled to Bennett to stay where she was and that they’d come over to her.

Knox and Williams reached the edge of the pavement at the same time as the double-decker momentarily blocked Bennett’s view of them. Then, when it had passed, Williams had vanished and Knox was lying in the gutter.

‘What the hell happened?’ Bennett shouted as she ran over the road and the bus turned round a corner and disappeared into Marylebone. ‘Where’s Williams?’

Knox pulled himself up, massaging the shoulder he’d landed on.

‘He’s gone,’ he said.

Chapter 20

Chapter 20

‘You’re sure it was him?’ Holland asked Knox.

After ten minutes of questioning the director general’s voice was still an even balance of amazement and suspicion.

‘Yes,’ Knox replied. ‘Completely.’

He was sitting again in the single chair that faced Holland across his desk. There was no way he could’ve gone straight after Williams with Bennett on his tail, so he’d returned to Leconfield House.