Everyone brought themselves an inch straighter -- the junior officer and the two guards at the door and the sergeant who stood behind and to the left of Colonel Belyak. The sergeant was a short square man with a pock -- marked corpse -- coloured face, its eyes lost in hollows, its nose broken and its jaw skewed. He hadn't spoken since I'd been brought in here ten minutes ago. He watched Colonel Belyak when he asked me questions, and watched me when I answered them. He would be the one, this sergeant, who would be ordered to beat me up if I looked like playing the fool, or refused to give the information the Colonel was looking for, or in any way tried bitching him about.

'so you want the woman released.' Belyak watched me steadily with the polished black stones in his face.

'Yes.'

'Why?'

'Because she's innocent of any wrongdoing. She was set up.'

'Explain that for me.'

'she was set up as bait in the assassination of General Gennadi Velichko.'

He brought his head down a degree and left his eyes on mine, a mannerism I was beginning to understand. I'd caught his attention.

'Continue,' he said. His voice had the tonelessness of a surgeon's asking for another scalpel.

I must have moved on the chair, because it creaked. It was a straight -- backed kitchen chair and I'd noticed stains on it when the Colonel had told me to sit down. I've seen chairs like this one before, stained and gone in the joints; professional interrogators all over the world use the same tricks, and one of them is to sit the detainee down so that he has to look up at the other people, which makes him nervous, and so that he's conveniently positioned if they decide to make him still more nervous by smashing him backwards onto the floor, chair and all. They use the back of their fist or their boot or whatever they choose, and although I know how to stop that kind of thing right in its tracks I never do, unless there's a chance of turning the odds and getting clear.

Tonight there was no question of that: I'd come here of my own freewill.

'I'm not going to tell you very much at this stage, Colonel Belyak. First the woman has to be released. We shall need Chief Investigator Gromov here, won't we, for his authority.'

'He is on his way,' the Colonel said 'How long will it take him to get here?'

'Why do you ask?'

'Because we've got to hurry.'

Colonel Belyak lifted his head slightly, still watching me; I'd seen him do that before when I'd told him something he didn't intend to take.

'We have all night, Mr Shokin.' He used Gospodin, as Chief Inspector Gromov had done on the train when he'd questioned me; its closest equivalent in the West was 'Mr'. Tovarishch was out now in Russia, a quaint Leninist trapping. 'We have as long as I decide we shall have,' the Colonel said.

He was standing with his feet apart, the polish on his jackboots glinting in the light from the bare electric bulb overhead, his shadow huge against the wall. His hands were behind him, and there was nothing in them; they'd been empty when he'd come in here. There was nothing in the sergeant's hands either; he was a man who liked the feel of bone on flesh when he went to work, a former pugilist with the gloves off now and real toys to play with.

'I want you to realize,' I told the Colonel,' that you're going to be very pleased indeed with the information I shall be giving you eventually, once Gospozha Rusakova has been released. I'm not setting any kind of deadline, you see; it's just a fact of life: we can't afford to waste any time.'

Not in fact true. Certainly I was setting a deadline, because I had to keep up the pressure. If I gave these people all the time they wanted they'd simply put me through intensive interrogation and I'd come out days later with not much more than pulp where the flesh had been, with a torn urethra and clouded conjunctivae and the kidneys contused and pouring blood into the urine and my sight gone and my brain out of synch and Meridian blown to hell.

There was also the risk of Tanya Rusakova's brother losing patience. I'm no good at waiting, doing nothing, he'd said on the telephone. If I'm not there -- at the rendezvous -- it will mean I changed my mind.

He could wreck everything I was trying to do.

'If there were any deadlines to be set,' Colonel Belyak was saying,' I would set them myself.'

'Of course.'

He was touchy and I'd have to watch it. I had begun paying out a thread so fine that one wrong word could break it.

'Tell me what you know,' the Colonel said, 'about the assassination of General Velichko.'

There was the sound of snow -- chains locking across concrete outside the building and the slamming of doors, so I took a chance and left the question unanswered, turning my head as the tramping of boots loudened and voices began echoing along the passage and Chief Investigator Gromov came in, shouldering his way between the guards and nodding briefly to the Colonel and staring down at me with his hands dug into the pockets of his coat.

'So we have you.'

Cold air was still coming in from the passage, laced with exhaust gas.

'Not quite that,' I said. .

'What, then?'

I missed the patience in his caramel -- brown eyes that I'd seen on the Rossiya. He'd had all the time he needed, then, but now he was more energized: he'd thrown a net across the city of Novosibirsk and here suddenly was the minnow, squirming, and he wanted facts and he wanted them fast.

'I decided to come here of my own free will,' I told him, 'to obtain the immediate release of Tanya Rusakova. She did nothing wrong, intentionally, and I want her out of here.' I spoke carefully, articulating; it wasn't a time for misunderstandings. 'I will then deliver into your hands -- if it's not too late -- the man who shot Zymyanin on board the Rossiya the night before last, who also set a bomb in one of the compartments with the intention of killing General Velichko, General Chudin and General Kovalenko, and -- having failed -- shot General Velichko to death last night in the street'

The cell was very quiet. There were telephones ringing in the offices along the passage, and boots sounded constantly over the bare boards.

'Shut that door,' Colonel Belyak told one of the militiamen, 'and stay on guard outside.' He swung his head to look at Gromov, wanting to tap into his thinking, but Gromov had his eyes on me.

'In the case of Zymyanin,' he said, 'you had witnesses against you on the train.'

'They were lying. But please remember that I just told you I can deliver the actual perpetrator if there is time.' I gave it a beat. 'When I last talked to him --' I checked my watch --' forty -- two minutes ago, he was making plans to set another bomb.'

Colonel Belyak was first. 'Where?'

'I can't tell you. He thinks he knows where the other two generals are, and he still means to kill them.'

'Do you know where they are?' Gromov asked quickly.

'No. I asked him but he refused to tell me.'

Belyak: 'Who is this man?'

I looked at my watch again. 'With respect, gentlemen, you will have to use your heads. I can't give you this man if we stay here talking. Nor can you hope to stop another tragedy like the one on the Rossiya, with further loss of innocent lives. The responsibility is yours.'

Silence came in again. It was warm in here with so many bodies, and the sweat was beginning to run on me. The thread was still intact, but I'd have to go on playing it out in the hope of drawing them with me, and there'd be a lot of strain.

'Why should we release this woman?' the Colonel asked.

'Because she's done nothing. She --'

'That's beside the point. Why do you want her released?'

'she's been traumatized by the whole thing and --'

'The "whole thing"?'

'Velichko's death.' He was right: I'd stopped choosing my words and we couldn't afford misunderstandings. 'You may consider it beside the point that you're holding an innocent person here and putting her through further suffering but I do not. The release of Tanya Rusakova is my only condition, but if you don't meet it I won't deliver the agent into your hands. But of course he could have left his base by now.'