‘I’m forty-one.’ No need to add anything; just answer the question. Sound respectful, but not too much. Don’t sound as if you’re in a hurry, but neither as if you have all day.

‘What day were you born?’

‘Eighth of July 1901.’

‘That’s not what I asked. I asked what day you were born; what day of the week.’

One or two identity cards in occupied Europe state the day you were born, but most don’t, and it’s a favourite trick of the Gestapo to ask. They’ll check it out. Best not to get it wrong, old chap, eh? If you’ve forgotten or aren’t sure, say you don’t know. You may just about get away with that; surprising how many people don’t know which day of the week they were born on.

‘A Monday. My mother always said she spent the whole weekend—’

The Gestapo officer held up his hand like a traffic policeman: stop. He was consulting something behind his desk, evidently checking whether 8 July 1901 was indeed a Monday.

Looking slightly disappointed, he thrust Peter Rasmussen’s papers back at him. ‘Very well, continue.’

Chapter 11

Berlin, December 1942

Tempelhof had been nerve-racking. Although he’d steeled himself for it, passing through the airport’s various layers of security felt like climbing an uncharted mountain: he’d reach a ridge and discover he was still in the foothills.

He recalled Hendrie telling him how important it was to adopt a frame of mind that there was nothing about him that could cause people to be suspicious, while at the same time remaining alert.

At the time he’d thought that would be easier said than done, and so it proved.

‘At least we’re past the first hurdle, eh?’ The U-Bahn train was almost deserted on the short journey from the airport to Koch Strasse station: just three stops up from Flughafen, then a short walk to their hotel. He was quickly put in place by Agent Horatio.

‘I’ve told you, be careful.’ Knudsen looked furious, his angry whisper just audible above the metronomic sound of the wheels on the track. He stared out of the window rather than at Prince. ‘Keep quiet until we’re somewhere safe. Believe it or not, getting into Germany is the easy part. The real danger begins once you’re in the country – and when you try to leave it.’

Agent Horatio’s instructions not to discuss anything about their mission during the flight had turned out to be academic. Despite sitting in one of the rear rows, the considerable noise from the two wing-mounted engines close to the cockpit rendered any conversation near impossible.