It would depend on what Ignatov had told them. If he'd said I was a dissident trying to provoke others last night in the Star Cafe, a dissident with certain friends who would try getting Schrenk out of prison, I could manage what they would do to me. But if the inconceivable had happened and Ignatov had told them I was an agent from London then they'd take me through the full routine as they'd taken Schrenk, and I didn't know for certain if I could stand up to it as he'd managed to do, because I wasn't fresh in the field and the tensions of the last operation were still flickering in the nerves. I could break and if I broke I could blow London, the whole of what I knew.

'There…' said the woman in front of me, and leaned forward in her black shawls to gaze at the bright glass coffin with the exhibit inside it, either the preserved body or an effigy, it was impossible to tell. She began weeping quietly, but the line wouldn't stop for anyone and I had to nudge her, as the man behind me was nudging me. We went down the steps and made for the huge rectangle of the doorway, passing between the guards and reaching daylight. The snow fell softly over the square and over the dark moving figures, bringing its silence to the scene. I stayed with a group, talking to the woman and her son; she was still weeping quietly but he took no notice. The nearest policemen were fifty yards away; I could hear their voices under the dark sky.

'When do you expect to get your licence,' I asked Viktorovich, 'in sewage engineering?' I steered the two of them to the left, towards the history museum, keeping my head down to talk to the boy and holding the paper wad against the wound with my hand covering most of it, because the blood must have soaked through by this time.

'When they give it to me,' the boy said. 'I've passed my exams. It's a question of time.' He looked around him at the huge museum and the gilded domes. 'One day I'm going to live here, you know that? But you need a visa, and you can't get a visa without a job here, and you can't get a job here without a visa.' He kicked at the snow, thrusting his bare knuckly hands into his pockets.

The woman stopped weeping and gave a sigh, fumbling among her shawls for a handkerchief. 'It was beautiful,' she said, 'beautiful.'

I held her arm, keeping her in a straight line for the museum through the gap between the two policemen. I watched the ground.

'Look at this snow,' the boy said. 'I forgot to cover the tractor before we left this morning.'

The policeman on the left was questioning someone: I could hear his voice. It was the other one, on the right, who came suddenly across to us, the leather of his new boots creaking.

'You,' he said. 'Papers.'

Within a minute there were five or six of them round me, forming a circle.

'His face,' they kept telling each other. The first one had raised his arm and held it like that until a captain came up, the heels of his polished black boots clinking on the hard surface: I think they were iron-capped.

'His face, Captain,' the first one said.

'What have you done to your face?' The captain pulled my hand away and stared at the wound.

'I fell against some railings outside my apartment.'

'When?' His breath steamed against my face.

'An hour ago, when — '

'An hour ago. Did you have an accident?'

'Yes, I slipped on the snow — '

'Did you have an accident in your car?'

Others came up. Behind them I caught a glimpse of the woman in the shawls, staring at me with her bright eyes, shocked.

'When did he have the accident?' It was another captain.

'He's lying.'

'How did he tear his coat?'

'Papers. Show me your papers.'

I could feel blood trickling on my chin: the wound had opened when the captain had pulled my hand away.

'Kapista Kirov. That tells us nothing.' They came closer, gathering round like boys who'd found an injured animal. More of them came, and one of them said: 'He is the man I saw running away from the car.'

'Are you sure?'

'I was there! Of course I'm sure.'

They all started talking at once.

Capsule.

'Take him along. Four of you.'

'March!'

People stood perfectly still in the falling snow, watching us as we walked past them towards the roadway. Three Black Ravens had already pulled up alongside the kerb; their engines were still running. The rear doors of the nearest one swung open with a bang and I got to it when they hustled me inside: it was in my hand by the time I sat down on the padded bench.

The rear doors slammed and the steel bar was dropped across outside. Four of them sat with me, watching me but not talking.

'I don't understand,' I told the captain. 'I fell against some railings. You're making a mistake.'

'Perhaps.'

I went on talking to him, explaining that I wasn't the man they wanted. He shrugged at intervals. The box was in my hand but I hadn't decided yet. I couldn't get the capsule out while I was sitting here: they were watching me the whole time.

Dzerzhinsky Square, through the barred windows, and the Children's World department store. Then, just opposite, Lubyanka.

I had no information. The choice was simply heads or tails, black or white. Ignatov had known I was an agent and had told them so, or he hadn't. If he had known, and had told them, then I risked betraying London when they brought the pressure on and my system began overloading. If I wanted to avoid that risk, I would have to take the capsule within the next few seconds, and blow the fuse.

'You can open up!' the captain called out.

Hands hit the steel bar upwards against the rear doors.

Once inside Lubyanka I would be closely watched and meticulously searched, if they were doing their job. They would know there were two critical points at which an active intelligence agent is liable to take his capsule: within minutes of his arrest, and when the interrogation began breaking him. Woodison had done it; so had Racklaw; so had Fane. The pressure had got too much: not just the pressure of their last arrest and interrogation but of all the other arrests and interrogations they'd been through since they'd first gone eagerly into the field as younger men, brandishing their unbruised innocence. The pressure is accumulative.

'Out! ' the captain told me. Two of the men dropped from the rear of the van and two stayed behind. A dozen more were waiting for me outside, and two patrol cars swung through the heavy gates, pulling up alongside and spilling their crews.

There was another decision I had to make, within the next few seconds. If I didn't take the capsule I must get rid of it.

'Was he driving that Pobeda?'

'He says he fell against some railings.'

'Get Orlov here. He was in the van that crashed.'

'Come on, out! March!'

I dropped to the ground and made my first decision. If I became certain, three days from now, four days, five, that I couldn't protect London, there was the other way of blowing the fuse.

'Orlov! Is this the man you saw running from the Pobeda?'

'Yes, Captain!' His face peered into mine. 'This is the one!'

Bloody fool, I'd come out of the smash like a bat out of hell and he didn't have time to take anything in because the van had rolled over. He wanted the kudos.

'Get him inside!'

There was a drain grid at one side of the steps and I let it drop and waited to hear if it made any sound, metal on metal, that would be.audible above the tramp of their boots.

'Captain,' I said loudly, exasperated, 'you're making a mistake.'

'I don't think so. But we shall see.'

Green-painted walls, passages, doorways, uniformed clerks, a smell of leather, black tobacco, gun oil and the ancient smells that breathe from the walls of old buildings.