'Quite a surprise,' I said. 'I believe we're playing cards together this evening.'

'I'm so pleased you're joining us,' said Henry, and seemed genuinely pleased. 'This is what I call the real Berlin, what? The beautiful and cultured Frau Hennig here, and this wonderful chap Koch whom she's told me all about. These are the people one wants to meet, not the free-loading johnnies who come knocking at the door of your average embassy.'

Lisl was smiling; she understood enough English to know that she was beautiful and cultured. She tapped my arm. 'And wear a jacket and a tie, will you, Leibchen? Just to make your old Lisl happy. Just for once wear a nice suit, the one you always wear to see Frank Harrington.' Lisl knew how to make me look a bloody fool. I looked at Tiptree; he smiled.

We played cards in Lisl's study, a small room crammed with her treasures. This was where she did the accounts and collected the money from her guests. She kept her bottle of sherry here in a cupboard otherwise filled with china ornaments. And here, with its prancing angels and winged dragons, was the grotesque ormolu mantel clock that could sometimes be heard throughout the house chiming away the small hours. There was a picture of Kaiser Wilhelm over the fireplace; around it a slight brightness of the wallpaper showed it was the place where a larger signed photo of Adolf Hitler had hung for a decade that had ended with the family home becoming this hotel.

'I think the cards need a good shuffle,' said Lisl plaintively as she arranged in front of her the few remaining counters for which we gave fifty pfennigs each. Lisl's losses could not possibly come to more than the price of the bottle of sherry that between us we'd almost consumed, but she didn't like losing. In that respect and many others she was very berlinerisch.

The four of us were arranged round the circular-topped mahogany tripod table, at which Lisl usually sat to take her breakfast. The four chairs were also mahogany; superbly carved with Venetian-style figure-of-eight backs, they were all that was left of the sixteen dining chairs that her mother had so cherished. Lisl had been talking about the European royal families and the social activities of their surviving members. She was devoted to royalty and convinced of the divine right of kings, despite her frequently proclaimed agnosticism.

But now Lothar Koch had started one of his long stories. 'So what was I saying?' said Koch, who was incapable of shuffling cards and talking at the same tune.

'You were telling us about this most interesting secret report on the Dutch riots,' prompted Henry.

'Ah, yes,' he said. Lothar Koch was a small motheaten man, with dark-ringed troubled eyes and a nose far too large for his small sunken face. Mr Koch had a large gold Rolex wrist-watch and liked to wear spotted bow-ties in the evening. But his expensive-looking suits were far too big for him. Lisl said that they fitted him before he lost weight, and now he refused to buy any more clothes. I'm far too old to buy new suits, he'd told Lisl when he celebrated his seventieth birthday in a suit that was already too baggy. Now he was eighty-five, still shrinking, and he still hadn't bought any new clothes. Lisl said he stopped buying overcoats when he was sixty, Ja, ja, ja. There had been riots in Amsterdam. That was the start of it. That was 1941. Brandt came into my office soon after the riots…'

'Rudolf Brandt,' explained Lisl. 'Heinrich Himmler's secretary.'

'Yes,' said Koch. He looked at me to be sure I was listening. He knew I'd heard all his stories before and that my attention was apt to wander.

'Rudolf Brandt,' I confirmed. 'Heinrich Himmler's secretary. Yes, of course.'

Having confirmed that I was paying attention, Koch said, 'I remember it as if it was yesterday. Brandt dumped on to my desk this report. It had a yellow front cover and consisted of forty-three typewritten pages. Look what that fool Bormann has come up with now, he said. He meant Hitler, but it was customary to blame Bormann for such things. It's true Bormann had countersigned each page, but he was just the Head of the Party Chancellery, he had no political power. This was obviously the Fuhrer. What is it? I asked. I had enough paperwork of my own to read; I wasn't looking for another report to occupy my evening. Brandt said, the whole population of Holland is to be resettled in Poland.'

'Good God,' said Henry. He took a minuscule sip of his sherry and then wiped his lips with a paper napkin advertising König Pilsener. Lisl got them free. Tiptree had changed his clothes. Perhaps in response to Lisl's sartorial demands of me, he was wearing a white shirt, old school tie and a dark grey worsted suit of the type that is issued to really sincere employees by some secret department of the Foreign Office.

'Yes,' said Lisl loyally. She'd heard the story more times than I had.

'Eight and half million people. The first three million would include "irreconcilables", which was Nazi jargon for anyone who wasn't a Nazi and not likely to become one. Also there would be market-garden workers, farmers and anyone with agricultural training or experience. They would be sent to Polish Galicia and there create a basic economy to support the rest of the Dutch, who would arrive later.'

'So what did you tell him?' said Henry. He pinched the knot of his tie between finger and thumb, and shook it as if trying to remove a small striped animal that had him by the throat.

Mr Koch looked at me. He realized that I was the 'irreconcilable' part of his audience. 'So what did you say, Mr Koch?' I asked.

He looked away. My display of intense interest had not convinced him I was listening, but he continued anyway. 'How can we put this impossible strain upon the Reichsbahn? I asked him. It was useless to appeal to these people on moral grounds, you understand.'

'That was clever,' said Henry.

'And the Wehrmacht was preparing for the attack on the USSR,' said Mr Koch. 'The work that involved was terrible… especially train schedules, factory deliveries and so on. I went across to see Kersten that afternoon. It was showery and I went out without coat or umbrella. I remember it clearly. There was a lot of traffic on Friedrichstrasse and I was drenched by the time I got back to my office.'

'Felix Kersten was the personal medical adviser to Heinrich Himmler,' explained Lisl.

Koch said, 'Kersten was a Finnish citizen, born in Estonia. He wasn't a doctor but he was an exceptionally skilled masseur. He'd lived in Holland before the war and had treated the Dutch royal family, Himmler thought he was a medical genius. Kersten was especially sympathetic to the Dutch and I knew he'd listen to me.'

'Why don't you deal the cards,' I suggested. Koch looked at me and nodded. We both knew that if he tried to do it while continuing his story he would get his counting hopelessly muddled.

'It's a fascinating story,' said Henry. 'What did Kersten say?'

'He listened but didn't comment,' said Koch, tapping the edges of the pack against the table-top. 'But afterwards his memoirs claimed that it was his personal intervention that saved the Dutch. Himmler suffered bad stomach cramps and Kersten warned him that such a vast scheme as resettling the entire population of Holland would not only be beyond the capabilities of the German railways but, since it would be Himmler's responsibility, it could mean a breakdown in his health.'

'They dropped it?' said Henry. He was a wonderful audience, and Mr Koch basked in the attention Henry was providing.

Koch riffled the cards so that they made a sound like a short burst of fire from a distant MG 42. He smiled and said, 'Himmler persuaded Hitler to postpone it until after the war. By this time, you see, our armies were fighting in Yugoslavia and Greece. I knew there was no chance of it ever happening.'