'You can cut corners,' Fane said, 'yes.' We turned from the bridge into the Rausskaja nabareznaja towards the Bukarest, and the wind was less sharp. 'I simply want you to do it only if you have to.' He stopped and looked up at me again. 'I don't mind your being difficult, you see, if that's your character. But I don't want you to use it as a policy.'

I'd never had to spell out the parameters of a mission with my local control before. It unnerved me.

'They've never given me anyone,' I said carefully, 'who didn't turn out to be first class, even if we finished up hating each other's guts. All I ask is that you get me home alive. Even if it's the last thing you want to do.'

He went on watching me with his level eyes, perhaps not knowing whether I was being funny. 'From someone as boorish as you, I suppose that's a compliment.'

'Sorry. It must have slipped out.'

In the hotel lobby Fane picked up a message and used an outside line while I looked at a display of dolls in regional costumes and had the odd thought that there actually were children like this dancing somewhere on some village square to the music of a pipe band while I stood here living my lies and practising my deceits on the pretext that I was doing my bit to keep the Cold War from hotting up. Which was the real world, those children's or mine? It can only ever be the one we create, the one we have to design for ourselves to give us shelter from confusion and sustenance for our needs. I don't dance so well to a pipe band as to the tune of my own dark drummer.

Fane was coming away from the telephone.

'They've put us on the quota. We're flying to Murmansk.'

'When?'

'As soon as they've got the runways cleared up there. They've had snow.'

Night was coming to Murmansk. There had been no sun. This was winter. The light was changing from steel grey to gunmetal blue, so slowly that it mesmerized. Shadows deepened as the weight of the dark came down, because the light wasn't leaving; it was simply changing, from the monotone arctic wash of the daytime, sunless and moonlike, to the trembling and fragile glow of the northern lights across the snow.

Only here, and in places along this latitude, does die coming of the night bring shadows. In its strangeness there is a certain quality of safety, if you are being watched: you can find concealment in the kaleidoscope of light and shade. And if you are watching, you can more easily detect abnormal configurations among the formal geometry of streets and buildings, such as the shape of a man's head.

Tonight I was watching. Soon I would know if I were also being watched.

The last I'd seen of Fane, an hour ago, was his short neat body with its swinging walk disappearing into die lift at die hotel. I was glad to see him go. In the days ahead I would need him, of course, perhaps desperately; but if I could make my way through this mission without his help I would like to do that.

There was something wrong about him. There was some-tiling wrong about their not giving me Ferris. I knew this without questioning how I knew, just as I knew without any question that the man at the end of the platform had missed the last train. But I didn't want to pay too much attention to there being something wrong until I knew more about North-light. That was the name across the top of the board at London Control, the name for the mission. It could still be a matter of nerves, though I'd been long enough in this trade to know that your nerves will tell you things more accurately, on a primitive level where sensitivity is subconscious, than your brain, which can make up answers of its own to explain the inexplicable, rather than admit to having none.

When the next train came in, its steam clouding against the pale luminosity of the sky and its hot smell reaching me and bringing warmth, I saw the man get into a carriage and slam the door. He hadn't, then, missed the last train: it wasn't going where he wanted to go, that was all.

'My name is Tanya.'

You can't tell much over a telephone. Her voice had been low, a little husky, that was all. But there'd been caution in the tone, a note of vigilance. There'd been silences, after I'd spoken, in which she had listened a second time to what I'd said, sifting it for danger.

'Why did you want me to telephone?' I asked her.

'Because of…' she'd hesitated, 'the snowbirds.'

She should have brought it in straight away, the moment she'd told me her name; but perhaps some idiot at the embassy hadn't told her that; or she'd forgotten. 'Snowbirds' was the code-introduction.

'What do you want me to do?' I asked her.

'To meet me.'

'Why?' This was routine. I already knew, but I wanted her to go on talking in case there were anything wrong, anything dangerous.

'Because-' she hesitated again — 'because of the snowbirds. That is all I can say, over the telephone.'

'All right. In an hour, then.'

'Very well.' She didn't ask where. They'd told her that it was for me to make the rendezvous. She was getting things right.

'At the east railway station,' I told her. 'How far is that from where you are now?'..'Not far. Perhaps five kilometres.'

'All right. In the small waiting-room at the north end of Platform 4. Repeat that.'

When she'd finished I said: 'Tell me what you look like.'

She hesitated again. 'I am young, and not very tall. I will be wearing an old sable coat, and-'

'What colour are your eyes?' Everyone here was wearing fur; it was twenty-five degrees below freezing.

'They are dark.'

'Brown? Blue?'

'Brown.'

'All right. Don't approach anyone. I'll approach you. Wear an odd pair of gloves, that don't quite match.'

That had been an hour ago and as the train pulled out I saw the man opening a paper behind the grimy glass. He didn't glance out.

In this unearthly light the station had the aspect of an illusion. With the snow-covered roofs reflecting the sky and the shadows darker than they'd been at noon, definition was lost, and the shadows seemed more solid than the buildings themselves. Her short figure had the same sense of unreality: her shadow, moving across the open expanse of snow between the lamps, leaned and turned with a movement of its own as the light changed around it.

I let ten minutes go by after she'd walked into the little waiting-room, checking and double-checking the configurations in the environment: the line of three taxis alongside the iron railings; the black Pobeda with snow on its roof, parked facing the gates; the two men talking near the cafeteria, their breath clouding under the lamps; the group of children stamping their feet to a rhythm that was becoming a dance and leading to laughter; and the sailors over by the huge red tea-wagon. It had taken me fifteen minutes to get here from the hotel and the rest of the time I'd spent absorbing the changing patterns of movement in the whole of the area overlooking the waiting-room, and I was satisfied.

London doesn't warn you to take care when it sends you into a rendezvous. It's your responsibility to check the other party for surveillance and for traps: you're expected to go in and get out and leave no trace, but we don't look at it as a tactical regulation because if we get anything wrong it's our own skin.

'Good evening.' I stood looking down at her for a moment.

She turned quickly to face me, half-catching her breath, her bronze eyes staring into mine with something like fear. She brought her hands upwards across the front of her worn sable coat as if protecting herself, though it was probably to show me her gloves didn't match.

'I thought you weren't coming,' she said huskily.

'Sorry I'm late. It was the snow.'

'Did you-' she left it.