There was a frightening ingenuity in Weisthor’s solution. After murdering the girls, all of whom had been selected for their Aryan looks, their bodies were hidden so carefully as to be virtually impossible to find: the more so when one took into account the lack of police manpower available to investigate something as routine as a missing person. By the time the police realized that there was a mass-murderer stalking the streets of Berlin, they were more concerned with keeping things quiet so that their failure to catch the killer did not look incompetent — for at least as long as it took to find a convenient scapegoat, such as Josef Kahn.

But what of Heydrich and Nebe, I wondered. Was their attendance at this SS Court of Honour deemed mandatory merely by virtue of their senior rank? After all, the S S had its factions just like any other organization. Daluege, for instance, the head of Orpo, like his opposite number Arthur Nebe, felt as ill-disposed to Himmler and Heydrich as they felt towards him. And quite clearly of course, Weisthor and his faction were antagonistic towards ‘the Jew Heydrich’. Heydrich, a Jew. It was one of those neat pieces of counter-propaganda that relies on a massive contradiction to sound convincing. I’d heard this rumour before, as had most of the bulls around the Alex, and like them I knew where it originated: Admiral Canaris, head of the Abwehr, German Military Intelligence, was Heydrich’s most bitter opponent, and certainly the most powerful one.

Or was there some other reason why Heydrich was going to Wewelsburg in a few days? Nothing to do with him was ever quite what it seemed to be, although I didn’t doubt for a minute that he would enjoy the prospect of Himmler’s embarrassment. For him it would be nice thick icing on the cake that had as its main ingredient the arrest of Weisthor and the other anti-Heydrich conspirators within the SS.

To prove it, however, I was going to need something else besides Weisthor’s papers. Something more eloquent and unequivocal, that would convince the Reichsfuhrer himself.

It was then that I thought of Reinhard Lange. The softest excrescence on the maculate body of Weisthor’s plot, it certainly wasn’t going to require a clean and sharp curette to cut him away. I had just the dirty, ragged thumbnail that would do the job. I still had two of his letters to Lanz Kindermann.

Back at the Alex I went straight to the duty sergeant’s desk and found Korsch and Becker waiting for me, with Professor Illmann and Sergeant Gollner.

‘Another call?’

‘Yes, sir,’ said Gollner.

‘Right. Let’s get going.’