Hanne and Prince looked at each other, still unsure of the point of the story.

‘Frankly, his tale sounded ridiculous, like some cheap detective thriller: he said he was to meet a one-armed man who’d answer to the name “Kestrel”. To be honest with you, I assumed he’d made it up. My commanding officer said we were wasting our time with him and we should allow the Americans to confiscate the dollars and then send him back to Cologne and let our chaps there deal with him. But when you mentioned Kestrel, I put two and two together, though I could be wrong, of course, it could just be a coincidence.’

Prince had been making notes in his little black book. ‘Remind me of his name?’

‘Charles Falmer, last name spelt with an “l”.’

‘And where is he now?’

‘He’s in the American cells in the basement: would you like to meet him?’

Before they were due to meet Falmer, Hanne and Prince had a row. She felt their investigation was too chaotic and Prince asked her what on earth she meant.

‘In Berlin, I think we relied too much on the goodwill of the Russians.’

‘But they’re our allies, Hanne. I trust Gurevich; if it wasn’t for him, you—’

‘That’s the point – you trust him too much, you see him as your friend. I agree he’s very charming and I realise that if wasn’t for him I’d probably be dead, but the fact is, we’re not on the same side as them any longer, are we? I think we ought to have made more effort at the prison – we should have insisted on interrogating Alphonse Schweitzer once he’d given Rauter the Ferret’s real name, and then we should have asked the Russians not to shoot the man who killed Rauter.’

‘Klaus Böhme?’

‘Yes, they shot him the same day: surely he ought to have been interrogated? Maybe he could have told us something. I think we need to stop wandering around Europe being grateful for the opportunity to ask a few questions here and a few questions there. We need to treat this like a serious criminal investigation. Remember, I worked in the major robbery unit at Norrebro when I was in Copenhagen. I’m experienced in dealing with complex crimes, and that’s how I think we should treat this case. With respect, Richard, I know you’re a senior detective, but maybe this is more my kind of crime, so please do let me take the lead when we question Falmer.’

Charles Falmer – Charles Denton Falmer, according to his papers – appeared at first to be grateful to see them, as if he believed they’d come to help him. It was an impression reinforced by the way Prince began the questioning, speaking in a friendly manner and checking Falmer’s details – name, date of birth, address in England, where he worked in Cologne and the facts surrounding his arrest. More than once he said ‘we ought to have this sorted in no time’, and each time he said it, Falmer seemed to relax a little more. He appeared not to have shaved for a couple of days and was stroking his stubble, still unused to the novelty of it.