On the floor of the cab, where the driver could not see it, was a copy of Neues Volk, the Nazi magazine of racial propaganda. Volodya picked it up, but did not read it.

‘Some idiot has set fire to a litter bin,’ said the driver.

‘Adlon Hotel,’ Volodya said, and the car pulled away.

He riffled the pages of the magazine and verified that a buff-coloured envelope was concealed within.

He longed to open it, but he waited.

He got out of the cab at the hotel, but did not go inside. Instead, he walked through the Brandenburg Gate and into the park. The trees were showing bright new leaves. It was a warm spring day and there were plenty of afternoon strollers.

The magazine seemed to burn the skin of Volodya’s hand. He found an unobtrusive bench and sat down.

He unfolded the magazine and, behind its screen, he opened the buff-coloured envelope.

He drew out a document. It was a carbon copy, typed and a bit faint, but legible. It was headed:

DIRECTIVE NO. 21: CASE ‘BARBAROSSA’

Friedrich Barbarossa was the German Emperor who had led the Third Crusade in the year 1189.

The text began: ‘The German Wehrmacht must be prepared, even before the completion of the war against England, to overthrow Russia in a rapid campaign.’

Volodya found himself gasping for breath. This was dynamite. The Tokyo spy had been right, and Stalin wrong. And the Soviet Union was in mortal danger.

Heart pounding, Volodya looked at the end of the document. It was signed: ‘Adolf Hitler.’

He scanned the pages, looking for a date, and found one. The invasion was scheduled for 15 May 1941.

Next to this was a pencilled note in Werner Franck’s handwriting: ‘The date has now been changed to 22 June.’

‘Oh, my God, he’s done it,’ Volodya said aloud. ‘He’s confirmed the invasion.’

He put the document back into the envelope and the envelope into the magazine.

This changed everything.

He got up from the bench and walked back to the Soviet Embassy to give them the news.

(ix)

There was no railway station at Akelberg, so Carla and Frieda got off at the nearest stop, ten miles away, and wheeled their bicycles off the train.

They wore shorts, sweaters, and utilitarian sandals, and they had put their hair up in plaits. They looked like members of the League of German Girls, the Bund Deutscher Mädel or BDM. Such girls often took cycling holidays. Whether they did anything other than cycle, especially during the evenings in the spartan hostels at which they stayed, was the subject of much speculation. Boys said BDM stood for Bubi Drück Mir, Baby Do Me.

Carla and Frieda consulted their map then rode out of town in the direction of Akelberg.

Carla thought about her father every hour of every day. She knew she would never get over the horror of finding him savagely beaten and dying. She had cried for days. But alongside her grief was another emotion: rage. She was not merely going to be sad. She was going to do something about it.