‘Perhaps more than once. Certainly Berlin, both inside and outside the Kabaret Lola. I suggest you talk – otherwise things will not go well for you. You know what – who – we want because you have been doing your damndest to hide him.’

Wilde had an interpreter with him in case of difficulties with the local Bavarian and Austrian dialects, but his presence was pointless, for nothing was going to come from the lips of Andreas Stock.

He fired questions at the killer for two hours, but got no reply. Finally, he ordered a doctor to be brought in to put a couple of stitches in his nose and lip, then tried one last time.

Wilde had gone equipped with cigarettes and when he slid them across they weren’t even acknowledged. Finally, he asked the interpreter to leave the room.

‘Herr Stock,’ he said now they were alone together, ‘you have one last chance. I know that you were ordered to murder the girl by her employer, Frau Boden. If you are prepared to talk to me and tell me all you know, I may be able to save you from the hangman’s noose. But you have to do this now because I won’t make this offer again, and nor will anyone else. You know we are looking for Julius Boden and, more than that, for Adolf Hitler. Help me with this.’

They were in a stone-walled cell with an iron bed, two wooden chairs and a small table. The air was chilly, but not as cold as the gaze of Andreas Stock, which remained directed to somewhere in the middle distance. He still said nothing. Wilde was thinking hard. In other circumstances, his instinct would be to go to Schwarzenkirche and bring Ilse Boden in for some tough interrogation. He had no doubt that she was behind the poor girl’s death.

But he couldn’t go there. He didn’t want her to know that her assassin was now languishing in a US Army cell block. He wanted her to think she was in the clear and unobserved, so that her son would feel secure and come to the village. And from there? He had to be their best hope of leading them to their ultimate target.

It was a long shot, but so was this whole quest.

Wilde walked out of the cell without another word to the prisoner. He slammed the iron door shut and told the guard to keep Stock in solitary. No visitors, no information from outside – and his presence was to be disclosed to no one apart from the girl’s family.