‘Not at all: it’s actually not too far from the hotel, near Friedrichstrasse. It turned out to be a very small restaurant, and rather cramped. Not long after we’d sat down, the manager asked if we’d be more comfortable upstairs, as our table was very narrow. It was a bit annoying, to be frank, because we’d just settled down. But we went upstairs and the room he showed us into had just the one table, quite large – you could have got eight people round it. It was a private dining room, apparently just for us. Even before we’d sat down, a man in uniform entered, not through the door we’d come in but through another entrance, one I hadn’t even noticed. He joined us at the table and Bruno introduced him. He said something like “This is my friend Kurt: he’s a Luftwaffe officer. He’s very interested to meet you” – words to that effect, anyway.’

‘And what happened then?’

‘We ordered our meal; it was a Bavarian pork stew, I recall. I’ve eaten better, but the beer was good – that was Bavarian too. Kurt asked me a lot of questions about the challenges of fabricating parts for engines that can withstand very high temperatures. Then he started to talk about how he had some understanding of the problem because he was involved in a programme to develop a pilotless aircraft – he never called it a rocket. I was quite unsure of how to react. He was certainly telling me things he shouldn’t have – you know all the detail, Peter, I gave it to you when we first met in Copenhagen. He left before us and said something about hoping we’d meet again. I know London have a lot of questions they want you to ask him, but I can’t guarantee we will get to meet him. Whatever happens, I can’t be seen to be pushing matters. We’ll go to the factory tomorrow and at some stage I’ll ask Bruno if he’ll have dinner with us. If it feels right, I’ll ask him if Kurt wants to join us.’

‘London will not be happy if I come all the way here and don’t get to see Kurt.’

‘I shouldn’t imagine they will be, but we’re very exposed here. We have to be careful. And you know what I was saying about your German?’

Prince nodded.

‘Don’t speak it at all and don’t let on you understand any. The fact that people will think you have no knowledge of the language may work to our advantage, you never know.’