The headquarters. The field headquarters of the Day Watch, set up to co-ordinate the hunt for me. Where else could the inexperienced Dark Magician have been expected to report his sighting of the quarry?

But I was walking straight into a set-up where there must be at least ten Dark Ones, including experienced guards. I was sticking my own head in the noose, and that was plain stupidity, not heroism – if I still had even the slightest chance of surviving. And I was very much hoping I did.

Seen from down below, under the concrete petals of its supports, the TV Tower was far more impressive than it was from a distance. But it was a certainty that most Muscovites had never been up to the observation platform and just thought of the tower as a natural part of the skyline, a utilitarian and symbolic object, rather than a place of recreation. The wind felt as strong as if I was standing in the aerodynamic pipe of some complex structure, and right at the very limit of my hearing I could just catch the low hum that was the voice of the tower.

I stood there for a moment, looking upwards at the mesh-covered openings, the shell-shaped hollows corroded into the concrete, the incredibly graceful, flexible silhouette. The tower really is flexible: rings of concrete strung on taut cables. Its strength is its flexibility.

I went in through the glass doors.

Strange. I'd have expected to find plenty of people wanting to view Moscow by night from a height of three hundred and thirty-seven metres. I was wrong. I even rode up in the lift all on my own, or rather, with a woman from the tower's staff.

'I thought there would be lots of people here,' I said, giving her a friendly smile. 'Is it always like this in the evening?'

'No, usually it's busy,' the woman said. She didn't sound very surprised, but I still caught a faint puzzled note in her voice. She touched a button and the double doors slid together. My ears instantly popped and my feet were pressed down hard against the floor as the lift went hurtling upwards – fast, but incredibly smoothly. 'Everyone just disappeared about two hours ago.'

Two hours.

Soon after my escape from the restaurant.

If that was when they set up their field headquarters, it wasn't surprising that hundreds of people who'd been planning to take a ride up to the restaurant in the sky on this warm, clear spring evening had suddenly changed their plans. Humans might not be able to see what was going on, but they could sense it.

And even the ones who had nothing to do with this whole business were smart enough not to go anywhere near the Dark Ones.

Of course, I had the young Dark Magician's appearance to protect me. But I couldn't be sure that kind of disguise would be enough. The security guard would check my appearance against the list implanted in his memory, everything would match up, and he would sense the presence of power.

But would he dig any deeper than that? Would he check the different kinds of power, check if I was Dark or Light, what grade I was?

It was fifty-fifty. He was supposed to do all that. But security guards everywhere always skip that kind of thing. Unless they just happen to be dying of boredom or they're new to the job and still keen.

But a fifty-fifty chance was pretty good, compared to my chances of hiding from the Day Watch on the streets.

The lift stopped. I hadn't even had time to think everything through properly, it had only taken about twenty seconds to get up there.

'Here we are,' the woman said, almost cheerfully. It looked pretty much like I was the Ostankino Tower's last visitor of the day.

I stepped out on to the observation platform.

This place was usually full of people. You could always tell straight away who'd just arrived and who'd already been there a while. From the uncertain way the new arrivals moved about, and how ludicrously careful they were when they approached the panoramic window, and the way they walked round the reinforced glass windows set in the floor and tested them timidly with their feet.

But this time it looked to me as if there were no more than twenty visitors. There were no children at all – I could just picture to myself the hysterics as they approached the tower, the parents' anger and confusion. Children are more sensitive to the Dark Ones.

Even the people who were on the platform seemed confused and depressed. They weren't admiring the view of the city spread out below them, with it lights glowing brightly – Moscow in its usual festive mood. Maybe it was a feast in a time of plague, but it was a beautiful feast. Right now, though, no one was enjoying it. Everything was dominated by the atmosphere of the Dark. Even I couldn't see it, but I could feel it choking me like carbon monoxide, no taste, no colour and no smell.

I looked down at my feet, pulled up my shadow and stepped into it. The guard was standing near me, just two steps away, on one of the glass windows set in the floor. He looked at me in a friendly sort of way, but slightly surprised. He obviously wasn't too comfortable hanging around in the Twilight, and I realised the other side hadn't assigned its best men to guard the field headquarters. He was young and well built, wearing a plain grey suit and a white shirt with a subdued tie – more like a bank clerk than a servant of the Dark.

'Ciao, Anton,' the magician said.

That took my breath away for a moment.

Had I really been that stupid? So ridiculously naive?

They were waiting for me, they'd lured me here, tossed another sacrificed pawn on to the scales, and even – God only knew how – drafted in someone who'd departed into the Twilight long, long ago.

'What are you doing here?'

My heart thumped and started beating regularly again. It was all very simple after all.

The dead Dark Magician had been my namesake.

'Just something I spotted. I need some advice.'

The guard frowned darkly. Not the right turn of phrase, probably. But he still didn't catch on.

'Spit it out, Anton. Or I won't let you through, you know that.'

'You've got to let me through,' I blurted out at random. In our Watch anyone who knew the location of a field headquarters could enter it.

'Oh yeah, who says?' He was still smiling, but his left hand was already moving down towards the wand hanging on his belt.

It was charged to full capacity. Made out of a shinbone with intricate carving and a small ruby crystal in the end. Even if I dodged or shielded myself, a discharge of power like that would bring every Other in the area running.

I raised my shadow again and entered the second level of the Twilight.

Cold.

Swirling mist, or rather, clouds. Damp, heavy clouds rushing along high above the ground. There was no Ostankino Tower here, this world had shed its final resemblance to the human one. I took a step forward through the damp, along an invisible path through the droplets of water. The movement of time had slowed – I was actually falling, but so slowly that it didn't matter yet. High above me the curtain of cloud was pierced by the light of three moons – white, yellow and blood-red. A bolt of lightning appeared ahead of me and grew, sprouting branches that crept slowly through the clouds, burning out a jagged channel.

I moved close to the vague shadow that was reaching for its belt with such painful slowness. I grabbed the arm. It was heavy, unyielding, as cold as ice. I couldn't stop it. I'd have to burst back out into the first level of the Twilight and take him on face to face. At least I'd have a chance.

Light and Dark, I'm no field operative! I never wanted to end up in the front line! Give me the work I enjoy, the work I'm good at!

But the Light and the Dark didn't answer. They never do when you call on them. There was only that quiet mocking voice that speaks sometimes in every heart, whispering: 'Who ever promised you an easy life?'

I looked down at my feet. They were already about ten centimetres below the Dark Magician's. I was falling, there was nothing to support me in this reality, there were no TV towers or anything of the sort here – no cliffs that shape or trees that tall.

How I wished I had clean hands, a passionate heart and a cool head. But somehow these three qualities don't seem to get along too well. The wolf, the goat and the cabbage – what crazy ferryman would think of sticking them all in the same boat?

And when he'd eaten the goat for starters, what wolf wouldn't like to try the ferryman?

'God only knows,' I said. My voice was lost in the clouds. I lowered my hand and grabbed hold of the Dark Magician's shadow – a limp rag, a blur in space. I jerked the shadow upwards, threw it over his body and tugged the Dark One into the second level of the Twilight.

He screamed when the world suddenly became unrecognisable. He'd probably never been any lower than the first level before. The energy required for his first trip came from me, but all the sensations were quite new to him.

I braced myself on the Dark One's shoulders and pushed him downwards, while I crept upwards, pressing my feet down hard on his hunched back.

'Great Magicians climb their way up over other people's backs.'

'You bastard, Anton! You bastard!'

The Dark Magician still hadn't realised who I was. He didn't realise it until the moment he turned over on to his back, still providing support for my feet, and saw my face. Here, in the second level of the Twilight, my crude disguise didn't work, of course. His eyes opened wide, he gave a short gasp and howled, clutching at my leg.

But he still didn't understand what I was doing and why. I kicked him over and over again, trampling his fingers and his face with my heels. It wouldn't really hurt an Other, but I wasn't trying to do him any physical damage. I wanted him lower, I wanted him to fall, move downwards on all levels of reality, through the human world and the Twilight, through the shifting fabric of space. I didn't have the time or the skill to fight a full-scale duel with him according to all the laws of the Watches, according to all the rules that had been invented for young Light Ones who still retained their faith in Good and Evil, the absolute truth of dogma and the inevitability of retribution.

When I decided I'd trampled the Dark Magician down low enough, I pushed off from his spreadeagled body, leapt up into the cold, damp mist and jerked myself out of the Twilight.

Straight out into the human world. Straight on to the observation platform.

I appeared squatting on my haunches on a slab of glass, soaking wet from head to foot, choking in an effort to suppress a sudden cough. The rain of that other world smelled of ammonia and ashes.

A faint gasp ran round the room and people staggered back, trying to get away from me.

'It's all right,' I croaked. 'Do you hear? It's all right.'

Their eyes told me they didn't agree. A man in uniform by the wall, a security guard, one of the TV Tower's faithful retainers, stared at me stony-faced and reached for his pistol holster.

'It's for your own good,' I said, choking in a new fit of coughing. 'Do you understand?'

I let my power break free and touch the people's minds. Their faces started looking more relaxed and calm. They slowly turned away and pressed their faces against the windows. The security guard froze with his hand resting on his unbuttoned holster.

Only then did I look down at my feet. And I too froze in shock.

The Dark Magician was there, under the glass. He was screaming. His eyes had turned into round black patches, forced wide open by his pain and terror. The fingertips of one hand were imbedded in the glass and he was hanging by them, with his body swaying like a pendulum in the gusts of wind. The sleeve of his white shirt was soaked in blood. The wand was still there on the magician's belt, but he'd forgotten about it. I was the only thing that existed for him right now, on the other side of that triple-reinforced glass, inside the dry, warm, bright shell of the observation platform, beyond Good and Evil. A Light Magician, sitting above him and gazing into those eyes crazy with pain and terror.

'Well, did you think we always fight fair?' I asked. Somehow I thought he might be able to hear me, even through the thick glass and the roar of the wind. I stood up and stamped my heel on the glass. Once, twice, three times – it didn't matter that the blow wouldn't reach the fingers fused into the glass.

The Dark Magician jerked, trying to tug his hand out of the way of that crushing heel – a spontaneous, instinctive, irrational reaction.