She frowned. ‘Oh yes, I was forgetting. Haupthändler is planning to fly to London tonight. Forgive me if I sound naive, but exactly what are you going to do when you get there? Just walk up to him and whoever it is he’s taking with him and ask them how much they got for the necklace? Maybe they’ll just open their suitcases and let you take a look at all their cash, right there in the middle of Tempelhof.’

‘Nothing in real life is ever all that tidy. There never are neat little clues that enable you to apprehend the crook with minutes to spare.’

‘You sound almost sad about it,’ she said.

‘I had one ace in the hole which I thought would make things a bit easier.’

‘And the hole fell in, is that it?’

‘Something like that.’

The sound of footsteps in the outer office made me stop. There was a knock at the door, and a motorcyclist, a corporal in the National Socialist Flying Corps, came in bearing a large buff-coloured envelope of the same sort as the one I had consigned earlier to the waste-paper basket. The corporal clicked his heels and asked me if I was Herr Bernhard Gunther. I said that I was, took the envelope from the corporal’s gauntleted hands and signed his receipt slip, after which he gave the Hitler Salute and walked smartly out again.

I opened the Air Ministry envelope. It contained several typewritten pages that made up the transcript of calls Jeschonnek and Haupthandler had made the previous day. Of the two, Jeschonnek, the diamond dealer, had been the busier, speaking to various people regarding the illegal purchase of a large quantity of American dollars and British sterling.

‘Bulls-eye,’ I said, reading the transcript of the last of Jeschonnek’s calls. This had been to Haupthandler, and of course it also showed up in the transcript of the other man’s calls. It was the piece of evidence I had been hoping for: the evidence that turned theory into fact, establishing a definite link between Six’s private secretary and the diamond dealer. Better than that, they discussed the time and place for a meeting.

‘Well?’ said Inge, unable to restrain her curiosity a moment longer.

I grinned at her. ‘My ace in the hole. Someone just dug it out. There’s a meet arranged between Haupthandler and Jeschonnek at an address in Grünewald tonight at five. Jeschonnek’s going to be carrying a whole bagful of foreign currency.’

‘That’s a hell of an informant you have there,’ she said, frowning. ‘Who is it? Hanussen the Clairvoyant?’

‘My man is more of an impresario,’ I said. ‘He books the turns, and this time, anyway, I get to watch the show.’

‘And he just happens to have a few friendly storm-troopers on the staff to show you to the right seat, is that it?’

‘You won’t like it.’