'Soon,' said Fiona. 'Next week, or the week following.'

Mrs Dias came in to remove the plates and solicit praise and gratitude for her cookery; these were provided in abundance by Fiona, with Tessa echoing her every superlative.

'Senhor Sam?' To her I was always Senhor Sam; she never said Senhor Samson. 'Senhor Sam… he like it?' She asked Fiona this question rather than addressing it to me. It was rather like hearing Uncle Silas and Bret Rensselaer and Dicky Cruyer discussing my chances of escaping from Berlin alive.

'Look at his plate,' said Fiona cheerfully. 'Not a scrap left, Mrs Dias.'

There was nothing left because my share was one lousy drumstick and the wishbone. The greater part of the chicken stew was now spread out on kitchen foil in the garden, being devoured by the neighbourhood's cat population. I could hear them arguing and knocking over the empty milk bottles outside the back door. 'It was delicious, Mrs Dias,' I said, and Fiona rewarded me with a beaming smile that vanished as the kitchen door closed. 'Do you have to be so bloody ironic?' said Fiona.

'It was delicious. I told her it was delicious.'

'Next time, you can interview the women the agency send round. Maybe then you'd realize how lucky you are.'

Tessa hugged me. 'Don't be hard on him, Fiona darling. You should have heard George when the au pair dropped his wretched video recorder.'

'Oh, that reminds me,' Fiona said, leaning forward to catch my attention. 'You wanted to record that W. C. Fields film tonight.'

'Right!' I said. 'What time was it on?'

'Eight o'clock,' said Fiona. 'You've missed it, I'm afraid.'

Tessa reached up to put her hand over my mouth before I spoke.

Mrs Dias came in with some cheese and biscuits. 'I told him to set the timer,' said Fiona, 'but he wouldn't listen.'

'Men are like that,' said Tessa. 'You should have said don't set the timer, then he would have set it. I'm always having to do that sort of thing with George.'

Tessa left early. She had arranged to see 'an old schoolfriend' at the Savoy Hotel bar. That must be some school!' I said to Fiona when she came back into the drawing room after seeing her sister to the door. I always let her see her sister to the door. There were always sisterly little confidences exchanged at the time of departure.

'She'll never change,' said Fiona.

'Poor George,' I said.

Fiona came and sat next to me and gave me a kiss. 'Was I awful tonight?' she asked.

'Asinus asino, et sus sui pulcher - an ass is beautiful to an ass, so is a pig to a pig.'

Fiona laughed. 'You were always using Latin tags when I first met you. Now you don't do that any more.'

'I've grown up,' I said.

'Don't grow up too much,' she said. 'I love you as you are.'

I responded by kissing her for a long time.

'Poor Tess. It had to happen to her, didn't it. She's so muddle-headed. She can't remember her own birthday let alone the dates she met Giles. I'm so glad you didn't start shouting at her or want to list it all in chronological order.'

'Someone will eventually,' I said.

'Did you have a terrible day?' she asked.

'Bret Rensselaer won't let Werner use the bank.'

'Did you have a row with him?' said Fiona.

'He had to show me how tough you get after sitting behind a desk for fifteen years.'

'What did he say?'

I told her.

'I've seen you punch people for less than that,' said Fiona, having listened to my account of Rensselaer 's tough-guy act.

'He was just sounding me out,' I said. 'I don't take any of that crap seriously.'

'None of it?'

' Rensselaer and Cruyer don't think that Brahms Four has been turned – neither does the D-G, you can bet on that. If they thought he was working for the KGB, we wouldn't be debating which member of the London staff goes over there to put his neck in a noose. If they really thought Brahms Four was a senior KGB man, they'd be burying that Berlin System file now, not passing it around to get 'Immediate Action' tags. They'd be preparing the excuses and half-truths they'd need to explain their incompetence. They'd be getting ready to stonewall the questions that come when the story hits the fan.' I took the wine that Tessa had abandoned and added it to my own. 'And they don't have any worries about me either, or they wouldn't let me within a mile of the office while this was on the agenda.'

'They've got to deal with you, Brahms Four insists. I told you that.'

'What they really think is that Brahms Four is the best damned source they've had in the last decade. As usual, they only came to this conclusion when it looked like they were losing him.'

'And what do you make of this ghastly business with Trent?'

I hesitated. I was guessing now, and I looked at her so that she knew this was just a guess. The approach to Trent might be a KGB effort to penetrate the Department.'

'My God!' said Fiona in genuine alarm. 'A Russian move to access the Brahms Four intelligence at this end?'

'To find out where it's coming from. Brahms Four is one of the best-protected agents we have. And that's only because he did a deal with old Silas, and Silas stuck to his word. The only way they would be able to trace him would be by seeing the material we're receiving in London.'

'That's unthinkable,' said Fiona.

'Why?' I said.

'Because Giles could never get his hands on the Brahms Four material – that's all triple A. Even I have never seen it, and you only get the odds and ends you need to know.'

'But the Russians might not know that Giles couldn't get hold of it. To them he's senior enough to see anything he asks for.'

Fiona stared into my eyes, trying to see what was in my mind. 'Do you think that Brahms Four might have got word of a RGB effort to trace him?'

'Yes,' I said. 'That's exactly what I think. Brahms Four's demand for retirement is just his way of negotiating for a complete change in the contact chain.'

'It gets more and more frightening,' said Fiona. 'I really don't think you should go there. This is not just a simple little day trip. This is a big operation with lots at stake for both sides.'

'I can't think of anyone else they can send,' I said.

Fiona became suddenly angry. 'You bloody well want to go!' she shouted. 'You're just like all the others. You miss it, don't you? You really like all that bloody macho business!'

'I don't like it,' I said. It was true but she didn't believe me. I put my arms round her and pulled her close. 'Don't worry,' I said. 'I'm too old and too frightened to do anything dangerous.'

'You don't have to do anything dangerous in this business to get hurt.'

I didn't tell her that Werner had phoned me and asked me how soon I'd go back there. That would have complicated everything. I just told her I loved her, and that was the truth.