Father smiled tersely. ‘Since May, SAS have been building up dossiers on suspected war crimes committed against their men and other British commandos. Last month a team moved into a villa at Gaggenau, over in the French Zone, and started trying to track down the perpetrators in order to bring them to trial. Henry is part of that team.’ He nodded at the younger man, who smiled at me: for some reason, I wished he hadn’t.

‘Henry contacted me while he was on leave in London last month,’ Father continued. ‘He was concerned that some of the guilty parties could evade justice even if they were to be brought before a court. In cases where our men were out of uniform, their lawyers are bound to argue that the conventions did not apply. As a result, they may escape with light sentences, perhaps as little as five or ten years. Worse, some may not even come to trial at all: under the terms of Yalta, most Ukrainians, for example, are being sent back to the Soviet Union. Many of them will be killed on arrival, but the likes of Shashkevich survived the war against strong odds - if they have enough money or other influence, they may yet slip through the net.’

He stood up and walked over to the window. It looked onto a small garden, surrounded by a high wall. He turned back to face me.

‘Henry showed me six files, concerning the very worst offenders. As soon as I read them, I realized it was an intolerable situation: many of the victims were British officers, and we should do everything in our power to see they receive justice. I set about trying to get in contact with the PM, and when he gave the go-ahead, came out and secured these premises. Henry has helped prepare a lot of ground for the job I have in mind - unfortunately, his leave ends on Wednesday, and his absence from Gaggenau would be too conspicuous if he did not return. You, however, are off everyone’s radar, and that, to answer your question, is why you’re here. We will be working very much along the same lines as the team at Gaggenau, with one major distinction: we will not be bringing any of these men to trial. We will have very limited access to supplies, fuel and transport, but Henry has put together papers identifying both of us as members of a British war crimes investigation team, and those should be accepted everywhere apart from the Soviet Zone. Once Henry leaves, though, we are on our own. Do you have any questions?’

I wondered if the two of them had lost their minds and begun weaving fantasies; many were these days. But they didn’t look mad: that was the frightening thing.