'Some people are able to do something,' said Fiona, giving the sort of answer that seemed to be expected of her. 'Others talk and write. The world has always been like that. The dreamers are no less valuable, Martin.'

'Yes, I knew you'd say that,' he said. The way he said it scared her. There often seemed to be a double meaning – a warning – in the things he said. It could have meant that he'd known she'd say it because it was the right kind of banality: the sort of thing a class-enemy would say. She infinitely preferred to deal with the Russians. She could understand the Russians – they were tough professionals – but this embittered idealist, who was prepared to do their dirty work for them, was beyond her comprehension. And yet she didn't hate him.

'You know everything, Martin,' she said.

'What I don't know,' he admitted, 'is why you married that husband of yours.'

'Bernard is a wonderful man, Martin. He is brave and determined and clever.'

He puffed his pipe before replying. 'Brave, perhaps. Determined: undoubtedly. But not even his most foolish friends could possibly call him clever, Fiona.'

She sighed. They had been through such exchanges before. Even though he was twice her age he felt he must compete for her. At first he'd made sexual advances, but that was a long time ago: he seemed to have given up on that score. But he had to establish his own superiority. He'd even shown a bitter sort of jealousy for her father when she'd mentioned the amazing fur coat he'd given her. Any fool can make money, Martin had growled. And she'd agreed with that in order to soothe his ego and pacify him.

Only lately had she come to understand that she was as important to him as he was to her. When the KGB man from the Trade Delegation appointed Martin to be her father-figure, factotum and cut-out, they'd never in their wildest dreams hoped that she would wind up employed by the British Secret Intelligence Service. This amazing development had proceeded with Martin monitoring and advising her on each and every step. Now that she was senior staff in London Central, Martin could look back on the previous ten years with great satisfaction. From being no more than a dogsbody for the Russians he'd become the trustee of their most precious investment. There was talk of giving him some award or KGB rank. He affected to be uninterested in such things but the thought of it gave him a warm glow of pleasure: and it might prove an advantage when dealing with the people at the London end. The Russians respected such distinctions.

She looked at her watch. How much longer before the courier came? He was already ten minutes late. That was unusual. In her rare dealings with KGB contacts they'd always been on time. She hoped there wasn't trouble.

Fiona was a double agent but she never felt frightened. True, Moscow Centre had arranged the execution of several men over the previous eighteen months – one of them on the top deck of a bus in Fulham; killed with a poison dart – but they had all been native Russians. Should her duplicity be detected, the chances of them killing her were not great but they would get her to tell them all she knew, and the prospect of the KGB interrogation was terrifying. But for a woman of Fiona's motivation it was even worse to contemplate the nun of years and years of hard work. Years of preparation, years of establishing her bona fides. Years of deceiving her husband, children and her friends. And years of enduring the poisonous darts that came from the minds of men like Martin Euan Pryce-Hughes.

'No,' Martin repeated as if relishing the words. 'Not even his best friends could call Mr Bernard Samson clever. We are lucky you married him, darling girl. A really clever man would have realized what you are up to.'

'A suspicious husband, yes. Bernard trusts me. He loves me.'

Martin grunted. It was not an answer that pleased him. 'I see him, you know?' he said.

'Bernard? You see Bernard?'

'It's necessary. For your sake, Fiona. Checking. We make contact now and again. Not only me but other people too.'

The self-important old bastard. She hadn't reckoned on that, but of course the KGB would be checking up on her and Bernard would be one of the people they'd be watching. Thank God she'd never confided anything to him. It wasn't that Bernard couldn't keep a secret. His head buzzed with them. But this was too close to home. It was something that she had to do herself without Bernard's help.

'I suppose you know that they have given me this direct emergency link with a case officer?' She said it in a soft and suggestive voice that would have well suited the beginning of a fairy story told to a wide-eyed and attentive audience of five-year-olds.

'I do,' he said. He turned and gave her a patronizing smile. The sort of smile he gave all women who aspired to be his comrades. 'And it's a fine idea.'

'Yes, it is. And I shall use that contact. If you or Chesty or any of those other blundering incompetents in the Trade Delegation contact any of the people round me with a view to checking, or any other stupid tricks, they'll have their balls ripped off. Do you understand that, Martin?'

She almost laughed to see his face: mouth open, pipe in hand, eyes popping. He'd not seen much of that side of her: for him she usually played the docile housewife.

'Do you?' she said, and this time her voice was hard and spiteful. She was determined that he'd answer, for that would remove any last idea that she might have been joking.

'Yes, Fiona,' he said meekly. He must have been instructed not to upset her. Or perhaps he knew what the Centre would do to him if Fiona complained. Lose her and he'd lose everything he cherished.

'And I do mean stay away from Bernard. You're amateurs; you're not in Bernard's league. He's been in the real agent-running business from the time when he was a child. He'd eat people like you and Chesty for breakfast. We'll be lucky if he's not alerted already.'

'I'll stay away from him.'

'Bernard likes people to take him for a fool. It's the way he leads them on. If Bernard ever suspected… I'd be done for. He'd take me to pieces.' She paused. 'And the Centre would ask why.'

'Perhaps you're right.' Pretending indifference, the man got to his feet, sighed loudly and looked out of the window over the net curtain as if trying to see the road down which the messenger would come.

It was possible to feel sorry for the old man. Brilliant son of a father who had been able to reconcile effortlessly his loudly espoused socialist beliefs with a lifetime of high living and political honours, Martin had never reconciled himself to the fact that his father was an unscrupulous and entertaining rogue blessed with unnatural luck. Martin was doggedly sincere in his political beliefs: diligent but uninspired in his studies, and humourless and demanding in his friendships. When his father died, in a luxury hotel in Cannes in bed with a wealthy socialite lady who ran back to her husband, he'd left Martin, his only child, a small legacy. Martin immediately gave up his job in a public library to stay at home and study political history and economics. It was difficult to eke out his tiny private income. It would have been even more difficult except that, at a political meeting, he encountered a Swedish scholar who persuaded him that helping the USSR was in the best interest of the proletariat, international socialism and world peace.

Perhaps the cruellest jest that fate had played upon him was that after seeing his father thrive in the upper middle-class circles into which he'd shoved his way, Martin – educated regardless of expense – had to find a way of living with those working classes from which his father had emerged. His rebellion had been a quiet one: the Russians gave him a chance to work unobserved for the destruction of a society for which he felt nothing. It was his secret knowledge which provided for him the strength to endure his austere life. The secret Russians and, of course, the secret women. It was all part of the same desire really, for unless there was a husband or lover to be deceived the affairs gave him little satisfaction, sexual or otherwise.