But the sheer tedium of staying in the flat for a month took its toll. Prince would count the hours until Hanne’s next visit and worry if he thought she was late. Henry was never out of his thoughts: a love for his son that became more painful by the day, along with a growing sense of guilt that he’d abandoned him.

There were no fireworks in Copenhagen that New Year’s Eve. There was some optimism in the city, as people read between the lines and realised Stalingrad was turning into a disaster for the Nazis. The more astute said this was the turning point of the war. Not long now – maybe this time next year!

New Year’s Day was a Friday, and Hanne appeared at the apartment that afternoon. She pushed away his advances: they had serious matters to talk about.

She’d heard from London and had made arrangements for his journey. She’d called in a number of favours. A friend of hers – someone she absolutely trusted – would drive him down to the island of Falster tomorrow. They would take him to the port of Gedser. There he would be handed over to a friend of this friend. The following day – Sunday – the second friend would get him into the docks, where an engineer called Peder would smuggle him onto the ferry. There he’d be hidden and would spend the night. On Monday the ferry would sail to Warnmünde, which was the port area of Rostock. When Peder told him it was safe, he’d leave the ferry and make his way to Rostock railway station, where he’d catch a train to Greifswald. Once there, he’d meet an agent called Blackbird.

‘Are these people you trust?’

‘The person taking you to Gedser I know well, I absolutely trust them.’

‘And the others – the friend in Gedser and this Peder?’

Hanne shrugged. ‘What can I say? I trust my friend and I have to assume the other two are trustworthy. But as I’ve said before, we can’t pretend this isn’t a dangerous game.’

‘And when I get to Germany, what identity do I use?’

‘You have plenty of Reichsmarks, that’s something.’

‘I wasn’t talking about money; I was talking about my identity.’

‘Take your Peter Rasmussen legitimationskort with you but keep it concealed – you’ll need it for when you get back. If you’re challenged, use this.’

It was an identity card for a German national: Ulrich Leuschner.

‘Seriously, Hanne? You think he looks like me?’

‘He has a beard.’

‘That’s about it.’

‘And the age is similar. It only needs to last one journey. It will have to do.’

‘Where did you get it from?’