Maxim looked at me again, and I saw the piercing glint of the Twilight in his eyes again. He was trying to see the lie, to see the Dark, to see the malice and hatred – the only things he was capable of seeing.

'You're not a Dark One,' he said. It was almost a complaint. 'I can see that. I've never been wrong, never!'

'I'm a watchman,' I repeated. I glanced around – there was no one to be seen. Something had frightened everyone away. That was probably one of the Maverick's powers.

'That boy . . .'

'He's an Other too,' I said quickly. 'It's not clear yet if he's going to be Light or—'

Maxim shook his head.

'He's Dark.'

I glanced at Egor. The boy slowly raised his eyes to meet mine.

'No,' I said.

I could see his aura quite clearly – bright, pure, shimmering colours, typical for very young children, but not for teenagers. His destiny was his own, his future was still undefined.

'He's Dark,' said Maxim, shaking his head again. 'Don't you see? I'm never wrong, never. You stopped me from exterminating an envoy of the Dark.'

He wasn't likely to be lying. He might not have been given many skills but the ones he had were powerful. Maxim could see the Dark, he could spot the tiniest hints of it in other people's souls. In fact, he saw the Dark that was just being born more clearly than any other kind.

'We don't just kill every Dark One we come across.'

'Why not?'

'We have a truce, Maxim.'

'But there can be no truce with the Dark.'

I shuddered. I hadn't heard the faintest note of doubt in his voice.

'Any war is worse than peace.'

'Except this one.' Maxim raised the hand holding the dagger. 'You see this? It was a present from a friend of mine. He was killed, maybe people like this boy were responsible. The Dark is cunning!'

'You think you need to tell me that?'

'Of course. You may be a Light One . . .' His face twisted in a bitter grin. 'But if you are, your Light faded a long time ago. There can be no forgiveness for Evil. There can be no truce with Evil.'

'No forgiveness for Evil?' Now I was really angry. 'After you stabbed the Dark Magician, you should have tried hanging around for another ten minutes. Or didn't you want to see his children screaming and his wife crying? They're not Dark Ones, Maxim. They're ordinary people who don't have our powers. You saved that girl they were shooting at. . .'

He flinched, but his face remained as implacably stony as ever.

'Well done! But did you know they were trying to kill her because of the crime you'd committed? Well?'

'This is war.'

'You've started your own war,' I whispered. 'You're like a child, with your toy dagger. You can't make an omelette without breaking eggs, is that it? No holds barred in the great struggle for the Light?'

'I don't fight for the Light,' he said in a quiet voice. 'I fight against the Dark. That's all I'm capable of. Do you understand? And you're wrong, it isn't a matter of eggs and omelettes for me. I didn't ask for this power, I didn't dream of having it. But since it has come to me, I can't act any other way.'

Just who was it who hadn't noticed him in time?

Why hadn't we found Maxim straight away, as soon as he became an Other?

He'd have made a first-class field operative. After long arguments and explanations. After months of training, after years of exercises, after tantrums, mistakes, bouts of drinking, attempts to kill himself. Eventually he would have understood the rules of the confrontation – not with his heart, he wasn't capable of that, but with his cold, uncompromising reason. The rules that govern the struggle between the Light and the Dark, that mean we have to turn a blind eye to werewolves hunting their victims and kill our own people who can't do that.

There he was, right in front of me. A Light Magician who'd killed more Dark Ones in a few years than a field operative with a hundred years of experience. Alone, cornered. Knowing only how to hate, incapable of love.

Egor just stood there quietly behind me, listening intently. I turned round, took him by the shoulders and pushed him in front of me. I said:

'Is he a Dark Magician? Probably – I'm afraid you're right. In a few more years, this kid will start to sense his own powers. As he goes through life, the Dark will creep alongside him. With every step his life will become easier and easier. And every step will be paid for by someone else's pain. Do you remember the fairy tale about the mermaid? A witch gave her legs, she could walk, but she felt like there were red-hot knives stabbing into her feet all the time. That story's about us, Maxim! We always walk over sharp knives, and that's something you can never get used to. But Hans Christian Andersen didn't tell the whole story. The witch could have done things differently: the mermaid walks, and the knives stab other people. That's the way of the Dark.'

'I carry my own pain with me,' said Maxim, and I suddenly felt an insane hope that he could understand after all. 'But that mustn't be allowed to change anything.'

'Are you prepared to kill him?' I said, nodding towards Egor. 'Tell me, Maxim. I'm a Night Watch agent, I know where the line runs between Good and Evil. You can create Evil, even by killing Dark Ones. Tell me – are you prepared to kill him?'

He didn't hesitate. He just nodded, looking straight into my eyes.

'Yes, I am, I've never let a creature of the Dark get away. I won't let this one get away.'

The invisible trap snapped shut.

It wouldn't have surprised me to see Zabulon standing there. To see him surface out of the Twilight and give Maxim a slap on the back. Or flash a mocking smile at me.

But a moment later I realised Zabulon wasn't there. He never had been.

The trap he'd set didn't need any supervision. It would work all on its own. I'd been caught, and every member of the Day Watch had a solid alibi for that moment.

I either had to let Maxim kill the boy who was going to become a Dark Magician and make myself into his accomplice – with all the obvious consequences.

Or fight the Maverick and kill him – I was far more powerful, after all. Eliminate the only witness with my own hand and kill a Light Magician into the bargain.

Maxim would never back down. This was his war, his own cross that he'd been carrying for years. He wanted victory or death.

So why should Zabulon bother to interfere in the fight?

He'd done everything right. Purged the ranks of the Dark Ones of useless ballast, built up the tension, even deliberately shot to miss. Zabulon had made me come to this spot to meet the Maverick. And now Zabulon was somewhere far away. Maybe not even in Moscow. He might even be watching what was happening: there were plenty of technical or magical devices he could use for that. Watching and laughing.

I was finished.

Whichever way I jumped, the Twilight was waiting for me.

Evil has no need to bother to eliminate Good. It's far simpler to let Good fight against itself.

I had just one chance left, a tiny one, but it was a monstrous, vile idea.

I could be too slow.

I could let Maxim kill the boy, or rather, simply fail to stop him. He'd calm down after that. He'd go to the Night Watch headquarters with me, listen, argue and eventually give up, crushed by the boss's implacable arguments and iron logic. He'd realise what he'd done and just how fragile the balance he'd disrupted was. And he'd hand himself over to the tribunal, where he had at least a slim chance of being acquitted.

I was no field operative, after all. I'd done everything I could. I'd even seen through the Dark's game, a sequence of moves devised by someone far wiser than me. I simply hadn't been strong enough, my reactions hadn't been fast enough.

Maxim raised the hand holding the dagger.

Time suddenly slowed down, as if I'd entered the Twilight. But the colours didn't fade, they became brighter than ever. It was like moving through a stream of thick syrup. The wooden dagger glided towards Egor's chest, changing as it moved, gleaming like metal or grey flame. Maxim's face was calm and intent, only the lip held beneath his teeth betrayed how tense he was. The kid didn't understand what was happening, he didn't even try to move out of the way.

I shoved Egor to one side – my muscles almost refused to obey me, they didn't want to do something so crazy and suicidal. For the boy, the young Dark Magician, the dagger meant death. For me, it meant life. That's the way it always has been and always will be.

What means life for a Dark One means death for a Light One, and vice versa. Who was I to change . . . ?

I wasn't too slow.

Egor fell, banged his head against the door and slid down into a sitting position – I'd pushed him too hard. But I was more concerned about saving him than any bruises he might get. Maxim's eyes glittered with almost childish resentment, but he could still talk.

'He's an enemy!'

'He hasn't done anything!'

'You're defending the Dark!'

Maxim wasn't arguing about whether I was Dark or Light. He could see that well enough.

It's just that he was whiter than white. And he'd never had to decide who should live and who should die.

The dagger was raised again. Not aimed at the boy this time, but at me. I dodged away, looked for my shadow, summoned it, and it came obediently towards me.

The world turned grey, sounds disappeared, movement slowed. Egor stopped squirming and became completely still, the cars crept along the street uncertainly, with their wheels turning in spurts, the branches of the trees forgot about the wind. But Maxim didn't slow down.

He'd followed me in, without knowing what he was doing. Slipped into the Twilight as easily as someone stepping off the kerb on to the road. It was all the same to him now, he was drawing strength from his own certainty, his own hatred, his lighter-than-light hatred, the fury of the colour white. He wasn't the executioner of the Dark Ones any longer. He was an Inquisitor. And he was far more terrifying than our Inquisition.

I threw my arms out, spreading my fingers in the sign of power, simple and foolproof – how the young Others laugh when they're shown that move for the first time. Maxim didn't even stop – he staggered a bit, then put his head down stubbornly and came for me again. I began to get the picture and backed away, desperately running through the magic arsenal in my mind.

Agape – the sign of love. He didn't believe in love.

The triple key – a sign that engendered trust and understanding. He didn't trust me.

Opium – a lilac symbol, the path of sleep. I felt my own eyelids starting to close.

That was how he defeated the Dark Ones. Combined with the powers of an Other, his furious faith acted like a mirror, reflecting back any blow aimed at him. It raised him up to his opponent's level. In combination with his ability to see the Dark and his ridiculous magical dagger, it made him almost invulnerable.

He couldn't reflect everything like that, though. The reflected blows didn't come back immediately. The sign of Thanatos – death – or the white sword would probably work.

But if I killed him, I'd kill myself. Set myself on the one road that we all come to in the end – into the Twilight. Into the faded dreams and colourless visions, the eternal, cold haze. He'd found it so easy to see me as an enemy, but I wouldn't be strong enough to see him that way.

We circled round each other, with Maxim sometimes making clumsy rushes at me – he'd never been in a real fight before, he was used to killing his victims quickly and easily. From somewhere far away I could hear Zabulon's mocking laughter. His soft, wheedling voice.