Whatever Goebbels and Hitler had done, their beautiful children had done nothing. Nor had the millions of other children who died or were maimed by the Nazis’ insane ambitions of world conquest. Wilde was not a superstitious man. He did not believe in the occult, nor even an afterlife, yet he could hear the children’s cries. He could feel the pain seeping through the concrete. He could smell the Zyklon B that killed mothers and babies and toddlers at Auschwitz, the carbon monoxide that killed young and old at Treblinka and Sobibor and Chelmno, and the bitter almonds of the cyanide that did for Heidrun, Hedwig, Holdine, Hildegard, Helga and their brother Helmut. The Goebbels children.

And he thought of his own boy, beautiful Johnny, full of laughter and joy back at home in Cambridge and his eyes filled with tears.

‘Come, Professor. It is too much here. We go, yes?’

Wilde nodded. He couldn’t speak.

On the way out, Minsky took Wilde’s arm and moved his mouth close to his ear. ‘One moment, Professor, let me show you this room.’ It was the largest room they had been in. ‘The diesel generators were here; we found a better use for them elsewhere.’ He lowered his voice again. ‘Can I trust you, Professor?’

‘I hope so – it depends what you want.’

‘You are a human being – I saw that just now. And I think we can help each other. No one is listening down here. Even our secret services cannot bug concrete four metres thick.’

‘The only help I want, comrade, is an interview with Günsche or Linge – or both. Or perhaps you also have Bormann?’

‘I’m sorry, that won’t happen. And no, we don’t have Bormann. Nor Dr Stumpfegger for that matter. Their disappearance is as mysterious to us as it is to you.’

‘What about the two dental technicians from Blaschke’s clinic? You told us they identified the bridge and jawbone as Hitler’s. Can I talk to them at least?’

He shrugged. ‘I know nothing about them. No, wait, I recall now – I’m afraid they too have been sent to Moscow. Anyway, their testimony was deemed unreliable.’ He sighed. ‘Look, I know I seem to be unhelpful, but these things are out of my hands. However, I do have access to another man who was here in the bunker until the very end. I think you might find him extremely helpful.’

‘Who is he?’

‘Hans Fritzsche, a senior official in the propaganda ministry. He has been in our custody in Moscow, but now he has been brought to Berlin because he will be standing trial with Goering and Ribbentrop and all the other senior Nazis at Nuremberg. He is a coward and he will do anything to save his skin. So he will talk.’

‘What has he told you?’