‘You’re lucky, Mister Churchill: you can’t trust all the slave labourers here, especially the Ukrainians, and I’m ashamed to say, not even us French. But my little group, most of us worked together in Tours: we’re socialists to a man. Just look tired as you go in. They’re so lazy, they only worry if there are people missing.’

Prince was astonished by the security around the camp. As they approached it, the ground around them was a sea of barbed wire, their route in a narrow path with the machine guns from the watchtower trained on it. Entering the camp itself was a lengthy process: he reckoned they went through half a dozen gates, each leading into a more secure area, but Émile had been right: all the guards were interested in was counting them and ensuring their group wasn’t smaller than when it had left the camp that morning.

‘Here, Mister Churchill – wake up! You’re now Pierre Breton. You even look a bit like him.’ It was the early hours of the morning and Émile was leaning over his bunk. ‘I knew they had a spare prisoner identity card in the next block; they got it from a prisoner who died. I had to give them two packets of cigarettes and my sausage. They’ll make sure Pierre Breton’s name is entered on the work list.’

So Richard Prince became Pierre Breton, a slave labourer. His first day at the camp was unusual, the others told him, because that night they were given what they considered to be a better meal than they’d had for a while. It was a strange stew, watery and oily at the same time, and the most identifiable ingredients were chunks of potato, more raw than cooked. Prince thought it was one of the most disgusting meals he’d ever tasted, but the others made him eat it. ‘We only get something like this a couple of times a week.’

They were right. The rest of the time it was a mug of soup, a hunk of stale bread and sometimes some jam. Within two days Prince felt the hunger gnawing away at his body and strange chilling sensations attacking his limbs. Food became his main obsession, so much so that he had to force himself to concentrate on what he was there for: to find out as much as he could about Peenemünde, and especially its layout.