‘We’ll need to see how—’

‘The RAF have taken over an airbase at Gatow in the south-west of the city, sir. I’ve already made some calls, and we can get on a flight there first thing in the morning if you approve it now.’

‘Both of you?’

‘Yes, both of us,’ Hanne said. ‘My German’s far better than Richard’s.’

‘Very well then. Let’s hope this isn’t going to be something I end up regretting, eh?’

The Dakota of RAF Transport Command left RAF Northolt at seven in the morning, landing at RAF Gatow in Berlin nearly four hours later. A tall man wearing a trilby and a long gabardine raincoat was waiting for them at the bottom of the aircraft steps. Hanne gripped Prince’s hand as they descended.

‘Is that the man?’

‘I imagine so.’

‘He looks like Gestapo.’

‘I doubt Gilbey’s employing former Gestapo officers, but we’ll soon find out.’

The man was called Kenneth Bemrose and was the best Gilbey could find at such short notice. He wasn’t MI6, but he had some kind of civilian role in the British Liaison Office, and most importantly he had security clearance. Almost as importantly – certainly as far as Prince was concerned – he also had use of a car, a khaki-coloured Humber Snipe with Union Jacks painted on the two front doors. Bemrose sounded rather put out when he explained he’d not been able to get hold of a driver so would be doing the honours himself, as he put it.

‘Here are your papers.’ He handed them a large brown envelope. ‘Not much, I’m afraid, but hopefully enough to get you through the checkpoints. They’ll impress our side more than theirs, but then that’s always the case. Where is it you want to go?’

‘Behrenstrasse. I’ll tell you which building once we’re there.’

‘I’m not terribly good at finding my way round the Soviet sector.’

Prince said not to worry, he’d be able to navigate.

They crossed the border at Potsdamer Platz, where the NKVD Border Guards officer in charge seemed unimpressed with their papers. He explained very slowly in basic German that it was most unusual to let people across if it was not a routine visit or if they didn’t have an appointment. He shook his head, and Bemrose muttered something about having told them so and whistled something jolly from a musical.

Hanne then spoke in Russian: it wasn’t very fluent, with a lot of pauses and gesticulating, but she smiled as she spoke and when the officer – clearly impressed – asked her something, Prince distinctly heard the word ‘Ravensbrück’ in her reply.

She turned to him. ‘Remind me of the name of the man we’re hoping to see?’

‘Iosif Leonid Gurevich, Podpolkovnik Gurevich: NKGB. We want to go to his office on Behrenstrasse.’

The officer straightened up and shouted orders to his men, and the barrier was raised.

‘I didn’t know you spoke Russian?’

‘We had Russian prisoners at the camp; I picked up a few words and the odd phrase from them. He seemed impressed when you mentioned Iosif.’