Barley Blair, he thought in amazement as he opened his wardrobe and hauled out the large aluminium hand-case where he kept his samples. Well, well. We often wondered whether we were nurturing a spy in our midst and now we know.

Landau's calm was absolute, he assured me. The Englishman had once more taken command of the Pole. 'If Barley could do it, I could, Harry, that's what I said to myself.' And it was what he said to me too, when for a short spell he appointed me his confessor. People do that to me sometimes. They sense the unrealised part of me and talk to it as if it were the reality.

Lifting the case on to the bed he snapped the locks and drew out two audio-visual kits that the Soviet officials had ordered him to remove from his display – one pictorial history of the twentieth century with spoken commentary which they had arbitrarily ruled to be anti-Soviet, one handbook of the human body with action photographs and a keep-fit exercise cassette, which, after gazing longingly at the pliant young goddess in the leotard, the officials had decided was pornographic.

The history kit was a glossy affair, built as a coffee-table book and containing a quantity of interior pockets for cassettes, parallel texts, progressive vocabulary cards and students' notes. Having emptied the pockets of their contents, Landau offered the notebooks to each in turn but found none large enough. He decided -to convert two pockets into one. He fetched a pair of nail scissors from his sponge bag and set to work with steady hands, easing the steel staples out of the centre divide.

Barley Blair, he thought again as he inserted the point of the nail scissors. I should have guessed, if only because you were the one it couldn't possibly be. Mr. Bartholomew Scott Blair, surviving scion of Abercrombie & Blair - spy. The first staple had come loose. He gingerly extracted it. Barley Blair, who couldn't sell hay to a rich horse to save his dying mother on her birthday, we used to say: spy. He began prising the second staple. Whose principal claim to fame was that two years ago at the Belgrade book fair he had drunk Spikey Morgan under the table on straight vodkas, then played tenor sax with the band so beautifully that even the police were clapping. Spy. Gentleman spy. Well, here's a letter from your lady, as they say in the nursery rhyme.

Landau picked up the notebooks and offered them to the space he had prepared but it was still not big enough. He would have to make one pocket out of three.

Playing the drunk, thought Landau, his mind still on Barley. Playing the fool and fooling us. Burning up the last of your family money, running the old firm deeper into the ground. Oh yes. Except that somehow or another you always managed to find one of those smart City banking houses to bail you out in the nick of time, didn't you? And what about your chess-playing then? That should have been a clue, if Landau had only had eyes for it! How does a man who's drunk himself silly beat all comers at chess then, Harry – straight games – if he isn't a trained spy?

The three pockets had become one pocket, the notebooks fitted more or less inside, the printed indication above them still read 'Student Notes'.

'Notes,' Landau explained in his mind to the inquisitive young customs officer at Sheremetyevo airport. 'Notes, you see, son, like it says. Student's notes. That's why there's a pocket here for notes. And these notes that you are holding in your hand arc the work of ah actual student following the course. That's why they're here, son, do you see? They are demonstration notes . And the drawings here, they're to do with the –'

With socio-economic patterns, son. With demographic population shifts. With vital statistics that you Russkies can never get enough of, can you? Here, seen one of these? It's called a body book.

Which might or might not save Landau's hide, depending on how smart the boy was, and how much they knew, and how they felt about their wives that day.

But for the long night ahead of him, and for the dawn raid when they kicked the door down and burst in on him with drawn pistols and shouted, 'All right, Landau, give us the notebooks!' for that happy moment, the kit wouldn't do at all. 'Notebooks, Officer? Notebooks? Oh, you mean that bunch of junk some loony Russian beauty pressed on me at the fair tonight. I think you'll probably find them in the rubbish basket, Officer, if the maid hasn't emptied it for once in her life.'

For this contingency also, Landau now meticulously set the scene. Removing the notebooks from the pocket of the history kit, he placed them artistically in the wastepaper basket exactly as if he had flung them there in the rage he had felt when he had taken his first look. To keep them company, he tossed in his surplus trade literature and brochures, as well as a couple of useless farewell gifts he had received: the thin volume of yet another Russian poet, a tin-backed blotter. As a final touch, he added a pair of undarned socks that only your rich Westerner throws away.

Once again I must marvel, as later we all did, at Landau's untutored ingenuity.

Landau did not go out and play that night. He endured the familiar imprisonment of his Moscow hotel room. From his window he watched the long dusk turn to darkness and the dim lights of the city reluctantly brighten. He made himself tea in his little travelling kettle and ate a couple of fruit bars from his iron rations. He dwelt gratefully upon the most rewarding of his conquests. He smiled ruefully 'at others. He braced himself for pain and solitude and summoned up his hard childhood to help him. He went through the contents of his wallet and his briefcase and his pockets and took out everything that was particularly private to him which he would not wish to answer for across a bare table - a hot letter a little friend sent him years ago that could still revive his appetites, membership of a certain video-by-mail club that he belonged to. His first instinct was to 'burn them like in the movies' but he was restrained by the sight of the smoke detectors in the ceiling, though he'd have laid any money they didn't work.

So he found a paper bag and, having torn up everything very small, -he put the pieces in the bag, dropped the bag out of the window and saw it join the rubbish in the courtyard. Then he stretched himself out on the bed and watched the dark go by. Sometimes he felt brave, sometimes he was so scared that he had to drive his fingernails into his palms to hold himself together. Once he turned on the television set, hoping for nubile girl gymnasts, which he liked. But instead he got the Emperor himself telling his bemused children for the umpteenth time that the old order had nd clothes. And when Spikey Morgan, half drunk at best, telephoned from the bar of the National, Landau kept him on the line for company till old Spikey fell asleep.

Only once and at his lowest point did it cross Landau's mind to present himself at the British Embassy and seek the assistance of the diplomatic bag. His momentary weakness angered him. 'Those flunkeys?' he asked himself in scorn. 'The-ones who sent my dad back to Poland? I wouldn't trust them with a picture postcard of the Eiffel Tower, Harry.'

Besides, that wasn't what she had asked him to do.

In the morning he dressed himself for his own execution, in his best suit, with the photograph of his mother inside his shirt.

And that is how I see Niki Landau still, whenever I dip into his file, or receive him for what we call a six-monthly top-up, which is when he likes to relive his hour of glory before signing yet another declaration of the Official Secrets 'Act. I see him stepping jauntily into the Moscow street with the metal suitcase in his hand, not knowing from Adam what's in it, but determined to risk his brave little neck for it anyway.

How he sees me, if he ever thinks of me, I dare not wonder. Hannah, whom I loved but failed, would have no doubt at all. 'As another of those Englishmen with hope in their faces and none in their hearts,' she would say, flushing with anger. For I am afraid she says whatever comes to her these days. Much of her old forbearance is gone.