‘The thing is,’ Dulles said, ‘we believe Collingham and Harper were closing in on Hitler. They had a contact and it’s likely they were on their way to meet him, or her. Unfortunately, we don’t have a name or location for this person.’

John Appache cut in: ‘Unfortunately Collingham and Harper weren’t good team players, if you know what I mean – very poor at passing on operational details. That’s why we don’t know their intended destination on the day they died.’

‘I can see your problem,’ Wilde said. Inside, he was thinking, but it’s not my problem.

‘To be honest, I don’t quite agree with Mr Dulles,’ Appache continued. ‘I never really believed Hitler was alive, and I thought Collingham and Harper were getting nowhere. But the murders of Randy and Denis suggest I was wrong. It is almost certain that they died because they were getting close, and Hitler’s protectors had to stop them in their tracks.’

‘I’m so sorry. It’s terrible news.’ Wilde felt sick to the pit of his stomach that a brave man like Collingham should have survived the war only to fall to an enemy bullet in the first months of the peace. The same for Denis Harper, a man he had met once but didn’t know well.

‘The killer left a taunting message,’ Dulles continued. ‘It said “Es lebe den Führer”. Written in block capitals on a piece of paper neatly deposited among the bloodstains on the rear seat.’

‘Long live the Führer.’ Wilde sighed; this was bloody grim news.

‘Also, strips had been torn off Collingham’s shirt. Makeshift bandages, perhaps?’

A thought struck Wilde. ‘Perhaps they were helping a man they thought was injured – a man who had smeared himself with blood. They put him in the back of the car to take him to hospital, then wham.’

Dulles nodded. ‘We had the same thought. Anyway, I don’t want Collingham and Harper to have died in vain. Nor do I want the mass murderer Adolf Hitler to evade justice. That’s why we’re here today. You can find him, Wilde.’

‘No.’ He shook his head firmly. ‘I’m very sorry, but none of this has anything to do with me, sad as I am at the loss of two good men. The war is over and I’m keen to return to some sort of normality. Anyway,’ he continued. ‘I ask again – why would you come to me?’

‘Well, you’re a historian,’ Dulles said. ‘And I know of no group of people less likely to have the wool pulled over their eyes than historians. You delve and you delve to get to some semblance of the truth – and even then you are sceptical. And rightly so in the case of Hitler. We have eyewitnesses who insist he died in battle in the Tiergarten, others who say he is in Spain, Brazil or somewhere in the Baltic.’

‘But you need an intelligence officer for this.’

‘That’s what you’ve been doing most of the war, isn’t it? And a great job, too, by all accounts.’