The Russians raped her: they raped all of us. She bled to death.

A notice on Herr Kühn’s door in Tiergarten said the apartment had been requisitioned by the British, and that he was staying with his daughter in Wedding, her address helpfully added.

‘Let’s go for a walk,’ Kühn said after Steiner had identified himself: I was wondering if you’d heard from my friend Graf – he was a former colleague of yours, I understand?

They walked silently onto a patch of wasteland – there were plenty to choose from – and sat on two chairs incongruously placed in the middle. Kühn insisted Steiner should call him Willi.

‘Look, I don’t know where Martin is and I’ve not had any contact with him.’ He was looking around nervously. ‘But I can tell you what I heard, though it’s third-hand, from someone who says he got it from another man who spoke to Axmann – I presume you know him?’

Steiner nodded. Of course he did: Artur Axmann, head of the Hitler Youth.

‘According to them, Axmann left the bunker on the first of May, the day after Hitler committed suicide. He was in a group that included Bormann and an SS doctor called Stumpfegger. They escaped through a U-Bahn tunnel as far as Friedrichstrasse, and then tried to cross the Spree on the Weidendammer Bridge to reach Lehrter station along the railway line, but because the Soviets were so close they decided to split up. Axmann was on his own and escaped, but it’s not clear what happened to Bormann and Stumpfegger.’

‘Where’s Axmann now?’

‘This man said he’s hiding in the Lübeck area, I’ve no idea if that’s true.’

‘So Bormann could still be alive?’

‘It’s certainly possible.’

The two men were walking back across the wasteland. ‘Can I ask how you knew the Reichsleiter?’ Steiner said.

‘Our mothers were great friends back in our home town in Saxony, and he and I grew up together, so when we both found ourselves in Berlin, we kept in touch, though increasingly less frequently. It was a relationship based on nostalgia, I guess. I’m not a political person, but when Martin approached me in March, I felt obliged to help an old friend.’

‘Of course.’

‘You’re Wolfgang Steiner, aren’t you?’

He stopped abruptly. ‘Martin told you?’

‘He confided in me – I got the impression he wanted to unburden himself. He even told me about the Kestrel Line and—’

‘He told you all that?’

The other man nodded, and Steiner said it would be best if he didn’t mention a word of this to anyone.

‘And where are you based now, Wolfgang – in case Martin turns up and wants to find you?’

For Steiner, that was one question too many. He wasn’t sure about this urbane schoolteacher who knew far too much.

‘Martin will know.’

‘But what if he contacts me and needs to get hold of you urgently?’

‘Memorise this telephone number, Willi – and don’t give it to anyone else, you understand? Only use it if there’s a message from Martin.’