Knox knew she was right. If Hoffman got his way, Williams would have to be carted off to prison, or somewhere worse, and a blindsided Holland would be hauled in front of the cabinet to explain the inexplicable.

‘Why are you here, then?’ he asked.

‘He’s still in my custody,’ Bennett replied, ‘until Hoffman makes his scene. I didn’t want you to find out what had happened after it was too late.’

‘How long do we have?’

‘Long enough to talk.’

Bennett’s hand reached out, but she stopped herself before she squeezed Knox’s arm in a gesture of un-spy-like empathy. Instead she just nodded at him and crossed over Ulster Terrace to where she could still see the bench but also give the two men a little privacy.

Knox watched her go, took a breath, and walked over to the bench and the best friend he never thought he’d see again. Up close, Williams looked older than the seven years that had passed. He was thinner, his hair longer and more lank than Knox had ever seen it. But it was definitely him.

Questions tumbled over each other in Knox’s head. There was so much he wanted to ask, so much he wanted to say. In the end, he sat down next to Williams and simply said, ‘It’s good to see you, Jack.’

‘It’s good to see you too, Richard,’ Williams replied.

The voice was unmistakable. That trademark tone of charismatic flippancy that ran through his well-educated Hertfordshire drawl. But Knox could detect a shadow of something else in it too now.

‘How are you?’ he asked.

‘I’ve been better,’ Williams replied. He smiled, but it looked more like a grimace.

‘Did the Americans treat you well?’

Williams looked down at the gravel path in front of the bench, and gripped both his arms, like he was trying to hold on to himself. ‘No.’

Knox looked at his fingers. They were bony and stained yellow. Williams had never smoked.

When he tilted his head back up, his eyes had completely changed. They weren’t calm any more. They were focused so fiercely on Knox it felt like they were boring straight through him, which they were, towards Bennett.

‘I asked her for help and they tortured me. You can’t trust her.’

‘You told Bennett you were the Wolf,’ Knox said, instantly regretting the insinuation he hadn’t intended.

‘I had to,’ Williams replied. ‘I had to make them think that so they’d want to know who I really was, then bring me back to you. So you could help me.’

‘Help you with what?’ Knox asked.

Williams leaned forward again, gripping his arms even tighter, as if the words he was about to say were physically trying to stop him from uttering them.