'Where's this safe house you keep exclusively for Polyakov?'

'Five, Lock Gardens, Camden Town.'

'With a caretaker?'

'Mrs McCraig.'

'Lately a listener?'

'Sure.'

'Is there built-in audio?'

'What you think?'

'So Millie McCraig keeps house and mans the recording instruments.'

She did, said Toby, ducking his head with great alertness.

'In a minute I want you to telephone her and tell her I'm staying the night and I'll want to use the equipment. Tell her I've been called in on a special job and she's to do whatever I ask. I'll be round about nine. What's the procedure for contacting Polyakov if you want a crash meeting?'

'My boys have a room on Haverstock Hill. Polly drives past the window each morning on the way to the Embassy, each night going home. If they put up a yellow poster protesting against traffic, that's the signal.'

'And at night? At weekends?'

'Wrong number phone call. But nobody likes that.'

'Has it ever been used?'

'I don't know.'

'You mean you don't listen to his phone?'

No answer.

'I want you to take the weekend off. Would that raise eyebrows at the Circus?' Enthusiastically, Esterhase shook his head. 'I'm sure you'd prefer to be out of it anyway, wouldn't you?' Esterhase nodded. 'Say you're having girl trouble or whatever sort of trouble you're in these days. You'll be spending the night here, possibly two. Fawn will look after you, there's food in the kitchen. What about your wife?'

While Guillam and Smiley looked on, Esterhase dialled the Circus and asked for Phil Porteous. He said his lines perfectly: a little self-pity, a little conspiracy, a little joke. Some girl who was passionate about him up north, Phil, and threatening wild things if he didn't go and hold her hand.

'Don't tell me, I know it happens to you every day, Phil. Hey, how's that gorgeous new secretary of yours? And listen, Phil, if Mara phones from home, tell her Toby's on a big job, okay? Blowing up the Kremlin, back on Monday. Make it nice and heavy, huh? Cheers, Phil.'

He rang off and dialled a number in north London. 'Mrs M., hullo, this is your favourite boyfriend, recognise the voice? Good. Listen, I'm sending you a visitor tonight, an old, old friend, you'll be surprised. She hates me,' he explained to them, his hand over the mouthpiece. 'He wants to check the wiring,' he went on. 'Look it all over, make sure it's working okay, no bad leaks, all right?'

'If he's any trouble,' Guillam said to Fawn with real venom as they left, 'bind him hand and foot.'

In the stairwell, Smiley lightly touched his arm. 'Peter, I want you to watch my back. Will you do that for me? Give me a couple of minutes, then pick me up on the corner of Marloes Road, heading north. Stick to the west pavement.'

Guillam waited, then stepped into the street. A thin drizzle lay on the air, which had an eerie warmness like a thaw. Where lights shone, the moisture shifted in fine clouds, but in shadow he neither saw nor felt it: simply, a mist blurred his vision, making him half-close his eyes. He completed one round of the gardens then entered a pretty mews well south of the pick-up point. Reaching Marloes Road he crossed to the western pavement, bought an evening paper and began walking at a leisurely rate past villas set in deep gardens. He was counting off pedestrians, cyclists, cars, while out ahead of him, steadily plodding the far pavement, he picked out George Smiley, the very prototype of the homegoing Londoner. 'Is it a team?' Guillam had asked. Smiley could not be specific. 'Short of Abingdon Villas, I'll cross over,' he said. 'Look for a solo. But look!'

As Guillam watched, Smiley pulled up abruptly, as if he had just remembered something, stepped perilously into the road and scuttled between the angry traffic to disappear at once through the doors of an off-licence. As he did so, Guillam saw, or thought he saw, a tall crooked figure in a dark coat step out after him, but at that moment a bus drew up, screening both Smiley and his pursuer; and when it pulled away, it must have taken his pursuer with it, for the only survivor on that strip of pavement was an older man in a black plastic raincoat and cloth cap lolling at the bus-stop while he read his evening paper; and when Smiley emerged from the off-licence with his brown bag, he did not so much as lift his head from the sporting pages. For a short while longer, Guillam trailed Smiley through the smarter reaches of Victorian Kensington as he slipped from one quiet square to another, sauntered into a mews and out again by the same route. Only once, when Guillam forgot Smiley and out of instinct turned upon his own tracks, did he have a suspicion of a third figure walking with them: a fanged shadow thrown against the broadloom brickwork of an empty street, but when he started forward, it was gone.

The night had its own madness after that; events ran too quickly for him to fasten on them singly. Not till days afterwards did he realise that the figure, or the shadow of it, had struck a chord of familiarity in his memory. Even then, for some time, he could not place it. Then one early morning, waking abruptly, he had it clear in his mind: a barking, military voice, a gentleness of manner heavily concealed, a squash racquet jammed behind the safe of his room in Brixton, which brought tears to the eyes of his unemotional secretary.

Probably the only thing which Steve Mackelvore did wrong that same evening, in terms of classic tradecraft, was blame himself for leaving the passenger door of his car unlocked. Climbing in from the driver's side, he put it down to his own negligence that the other lock was up. Survival, as Jim Prideaux liked to recall, is an infinite capacity for suspicion. By that purist standard Mackelvore should have suspected that in the middle of a particularly vile rush-hour, on a particularly vile evening, in one of those blaring side streets that feed into the lower end of the Elysees, Ricki Tarr would unlock the passenger door and hold him up at gun-point. But life in the Paris residency these days did little to keep a man's wits sharp, and most of Mackelvore's working day had been taken up with filing his weekly expenses and completing his weekly returns of staff for the housekeepers. Only lunch, a longish affair with an insecure anglophile in the French security labyrinth, had broken the monotony of that Friday.

His car, parked under a lime tree that was dying of exhaust fumes, had an extra- territorial registration and CC plastered on the back, for the residency cover was consular though no one took it seriously. Mackelvore was a Circus elder, a squat, white-haired Yorkshireman with a long record of consular appointments which in the eyes of the world had brought him no advancement. Paris was the last of them. He did not care particularly for Paris, and he knew from an operational lifetime in the Far East that the French were not for him. But as a prelude to retirement it could not be bettered. The allowances were good, the billet was comfortable, and the most that had been asked of him in the ten months he had been here was to welfare the occasional agent in transit, put up a chalkmark here and there, play postman to some ploy by London Station, and show a time to the visiting firemen.

Until now, that was, as he sat in his own car with Tarr's gun jammed against his rib- cage, and Tarr's hand resting affectionately on his right shoulder, ready to wrench his head off if he tried any monkey business. A couple of feet away, girls hurried past on their way to the Metro and six feet beyond that the traffic had come to a standstill: it could stay that way for an hour. None was faintly stirred by the sight of two men having a cosy chat in a parked car.

Tarr had been talking ever since Mackelvore sat down. He needed to send a message to Alleline, he said. It would be personal and decypher yourself and Tarr would like Steve to work the machine for him while Tarr stood off with the gun.

'What the hell have you been up to, Ricki?' Mackelvore complained, as they walked arm in arm back to the residency. 'The whole Service is looking for you, you know that, don't you? They'll skin you alive if they find you. We're supposed to do bloodcurdling things to you on sight.'

He thought of turning into the hold and smacking Tarr's neck but he knew he hadn't the speed, and Tarr would kill him.

The message would run to about two hundred groups, said Tarr, as Mackelvore unlocked the front door and put on the lights. When Steve had transmitted them they would sit on the machine and wait for Percy's answer. By tomorrow, if Tarr's instinct was correct, Percy would be coming over to Paris hotfoot to have a conference with Ricki. This conference would also take place in the residency, because Tarr reckoned it was marginally less likely that the Russians would try to kill him on British consular premises.

'You're berserk, Ricki. It's not the Russians who want to kill you. It's us.'

The front room was called Reception, it was what remained of the cover. It had an old wooden counter and out of date Notices to British Subjects hanging on the grimy wall. Here, with his left hand, Tarr searched Mackelvore for a weapon but found none. It was a courtyard house and most of the sensitive stuff was across the yard: the cypher room, the strong room and the machines.

'You're out of your mind, Ricki,' Mackelvore warned monotonously, as he led the way through a couple of empty offices and pressed the bell to the cypher room. 'You always thought you were Napoleon Bonaparte and now it's got you completely. You'd too much religion from your Dad.'

The steel message hatch slid back and a mystified, slightly silly face appeared in the opening. 'You can go home, Ben boy. Go home to your missus but stay close to your phone in case I need you, there's a lad. Leave the books where they are and put the keys in the machines. I'll be talking to London presently, under my own steam.'

The face withdrew and they waited while the boy unlocked the door from inside: one key, two keys, a spring lock.

'This gentleman's from out East, Ben,' Mackelvore explained as the door opened. 'He's one of my most distinguished connections.'

'Hullo, sir,' said Ben. He was a tall, mathematical-looking boy with spectacles and an unblinking gaze.

'Get along with you, Ben. I'll not dock it against your duty pay. You've the weekend free on full rates, and you'll not owe me time either. Off you go, then.'

'Ben stays here,' said Tarr.

In Cambridge Circus the lighting was quite yellow and from where Mendel stood, on the third floor of the clothes shop, the wet tarmac glistened like cheap gold. It was nearly midnight and he had been standing three hours. He stood between a net curtain and a clothes-horse. He stood the way coppers stand the world over, weight on both feet equally, legs straight, leaning slightly backward over the line of balance. He had pulled his hat low and turned up his collar to keep the white of his face from the street, but his eyes as they watched the front entrance below him glittered like a cat's eyes in a coal hole. He would wait another three hours or another six: Mendel was back on the beat, the scent of the hunt was in his nostrils. Better still, he was a night bird; the darkness of that fitting room woke him wonderfully. Such light as reached him from the street lay upside down in pale pieces on the ceiling. All the rest, the cutting benches, the bolts of cloth, the draped machines, the steam iron, the signed photographs of princes of the blood, these were there because he had seen them on his reconnaissance that afternoon; the light did not reach them and even now he could barely make them out.