The evening started off very sedately, as evenings were likely to do when Sir Giles Streeply-Cox was the guest of honour. A muscular old man with bushy white Pickwickian sideburns and a florid complexion, 'Creepy-Pox', had been the scourge of the Foreign Office in his day. Ministers and Ambassadors went in terror of him. Since retirement he lived in Suffolk and grew roses while his wife made picture frames for all the local watercolour artists. But the old man was still attending enough committees to get his fares and expenses paid when he came to London.

It was the first time I'd ever seen the fearful Creepy close-to, but this evening he was on his best behaviour. Cindy knew exactly how to handle him. She let him play the part of the charming old great man of Whitehall. He slipped into this role effortlessly but there was no mistaking the ogre that lurked behind the smiles and self-deprecating asides. Lady Streeply-Cox said little. She was of a generation that was taught not to mention the food or the table arrangements, and talking about her husband's work was as bad as talking about TV. So she sat and smiled at her husband's jokes, which meant she didn't have much to do all evening.

There were two Diplomatic Corps people. Harry Baxter, a middle-aged second secretary from our embassy in Berne, and his wife Pat. She had a heavy gold necklace, pink-tinted hair and told old jokes – with punch-lines in schweizer-deutsch – about bankers with unpronounceable names.

When Cindy asked Baxter what exciting things had been happening in Berne lately, old Streeply-Cox answered for him by saying the only exciting thing that happened to the diplomatic staff in Berne was losing their bread crusts in the fondue. At which both Streeply-Coxes laughed shrilly.

There was a young couple too. Simon was a shy young chap in his early twenties who'd been teaching English in a private school in Bavaria. It was not an experience he'd enjoyed. 'You see these mean little German kids and you understand why the Germans have started so many wars,' he said. 'And you see those teachers and you know why the Germans lost them.' Now Simon had become a theatre critic on a giveaway magazine and achieved a reputation as a perfectionist and connoisseur by condemning everything he wrote about. With him there was a quiet girl with smudged lipstick. She was wearing a man's tweed jacket many sizes too big for her. They smiled at each other all through dinner and left early.

After dinner we all went upstairs and had coffee and drinks in a room with an elaborate gas fire that hissed loudly. Creepy had one demi-tasse of decaffeinated coffee and a chocolate mint, then his wife swigged down two large brandies and drove him home.

The couple from Berne stayed on for another half-hour or so. Cindy having indicated that she wanted a word with me, I remained behind. 'What do you think of him?' she said after all the other guests had left.

'Old Creepy? He's a barrel of fun,' I said.

'Don't take him for a fool,' Cindy warned. 'He knows his way around.'

I had a feeling that Creepy was there to impress me with the sort of contacts she had, the sort of influence she could wield behind the scenes in the Foreign Office corridors if she needed a show of strength. 'Did you want to talk to me?'

'Yes, Bernard, I did.'

'Give me another drink,' I said.

She got the bottle of Scotch from the side-table and put it in front of me, on a copy of Nouvelle Cuisine magazine. On the cover it said, 'Ten easy steps to a sure-fire chocolate roulade'. She didn't pour it, she walked across to the fireplace and fiddled with something on the mantelpiece. 'Ever since poor Jim was murdered…' she began without turning round.

I suppose I guessed – in fact dreaded – what was coming because I immediately tried to head it off. 'Is murdered the right word?' I said.

She rounded on me. 'Two men wait for him and shoot him dead? Six bullets? What do you call it Bernard? It's a damned bizarre way to commit suicide, isn't it?'

'Yes, go on.' I dropped some ice into my glass and poured myself a generous drink.

'I asked about the funeral. I told them I wanted to go and asked them for the fare.'

'And?'

'It's all over and done with. Cremated.' She used the word as if it was an obscenity, as perhaps for her it was. 'Cremated! Not a word to me about what I'd like done for my husband.' Her voice was bitter. As a Catholic she felt herself doubly wronged. 'Oh, and there's something for you/

She gave me a cardboard box. I opened it and found a pile of papers about ancient Mesopotamian tomb inscriptions. It was all neatly arranged and included ones that Fiona had worked on. I recognized her handwriting. 'For me?' I said. 'In Jim's Will?'

'There was no Will; just a letter Jim had left with his lawyer. Things to be done after he died. It's witnessed. It's legal they say.'

'Are you sure he wanted me to have it? I was never interested.'

'Perhaps he wanted you to send it to Fiona,' she said. 'But don't give it back to me. I've got enough on my mind without all the tricks and puzzles of the Ancient World.'

I nodded. She'd always been sarcastic about Jim's hobby and I suppose I had too.

'I've been trying to find out more exactly what Jim was doing when he died,' she said and there was a significant pause.

'Tell me.' I knew she was going to tell me anyway.

'I started with the money,' she said. I nodded. The Foreign Office handled our budget. It was one aspect of our work that she might have been able to pry into.

'Money?' I said.

'The money that's supposed to be missing. The money you went to Washington to ask Jim about.'

'Just for the record, Cindy, I didn't go to Washington to ask Jim anything. That extra little job was dumped upon me after I got there.'

She was unconvinced. 'Maybe. Maybe not,' she said. 'When we've got to the bottom of it you might find that it was all arranged right from the start.'

'That what was arranged?'

'Having you in Washington at the right time to do that "little extra job".'

'No. Cindy…'

'Mother of God! Will you listen to me, Bernard, and stop interrupting. The fund that Jim arranged. There was a lot of money laundered through a couple of banks in Gibraltar and Austria. Backwards and forwards it went so it's damned difficult to trace it. It seems to have ended up in an account in Germany. All that money was moved and invested six months before your wife defected.'

'So what?'

'Before!'

'I heard you.'

'Don't you see?'

'See what?'

'Suppose I told you that this fund was set up by your wife Fiona? Suppose I said that this was a KGB slush fund?'

'A KGB what?' I said rather more loudly than I intended. 'And Jim could sign? You told me Jim could sign.'

She smiled knowingly. 'Exactly. That was the cunning of it. Suppose Fiona set up the funding of a KGB network and used SIS money and people to operate it? Do you see the elegance of it?'

'Frankly, no,' I said. I wasn't going to make it easy for her. If she wanted to sell me her crackpot hypothesis she'd have to take me through it theorem by theorem.

'Financing a secret network is the most difficult and dangerous part of any secret operation. You don't have to be working on your side of the river to know that, Bernard.'

'Yes, I think I read that somewhere,' I said. But sarcasm wasn't going to stop her.

'Don't be stupid, Bernard. I know how it all works.'

I drank her whisky and didn't answer.

'I must have a cigarette,' she said. 'I'm trying to give up but I must have one now.' She got an unopened pack from a brass bowl on the bookshelf and took her time lighting up. Her hands were shaking, and the flaming match emphasized the movement, but that might have been because she craved the cigarette. I watched her with interest. The people in the Foreign Office knew things that we never found out about until it was too late. She said, 'If Fiona set up a clandestine bank account and had our own people run it under strict secrecy, it would be the best and most secret way to supply funds to enemy agents wouldn't it?' She was calmer now that she was smoking the cigarette.