I started getting angry.

'Why would I need to bribe you? It's just stupid to throw it out, that's all. It's blood. People gave it to help someone.'

Kostya suddenly laughed. He reached out, took one of the bottles and opened it, tearing off the tinfoil cap with practised ease. He raised the bottle to his lips, laughed again and took a swallow.

I'd never seen them feed. And never really wanted to.

'Stop that,' I said. 'Don't play the fool.'

Kostya's lips were covered in blood and there was a fine trickle of it running down his neck. Not just running down, but soaking into the skin.

'Do you find the way we feed ourselves unpleasant?'

'Yes.'

'So you find me unpleasant as well? All of us?'

I shook my head. We'd never talked about this before. It had been easier that way.

'Kostya, in order to live, you need blood. And, sometimes at least, human blood.'

'We don't live.'

'I meant in the more general sense. In order to move, think, speak, dream.'

'What do you care about a vampire's dreams?'

'Listen, son. There are plenty of people living in the world who need regular blood transfusions. There are at least as many of them as you. And then there are hospital emergencies. That's why people give blood, that's why it's thought to be such an honourable and respected thing to do ... I know about your kind's contributions to the development of medicine and the way you promoted the giving of blood. Kostya, if someone needs blood in order to live, to exist – that's no big deal. And whether it goes in through the veins or the stomach is irrelevant too. The important thing is how you get hold of it.'

'Empty words,' Kostya snorted. I got the feeling he'd crossed over into the Twilight for an instant and then come straight back out. The boy was growing up, all right. And he was getting really strong.

'You showed the way you really feel about us yesterday.'

'You're wrong.'

'Ah, drop it . . .' He put the bottle down, then changed his mind and turned it upside down over the sink. 'We don't need your—'

I heard a hoot behind me and swung round. I'd completely forgotten about the owl, but now it had turned its head towards Kostya and spread its wings.

'Agh . . .' he said. 'What . . .'

The owl folded its wings and closed its eyes.

'Olga, we're talking,' I growled. 'Just give us a moment . . .'

The bird didn't respond. Kostya glanced from me to the owl and back again. Then he sat down and folded his hands on his knees.

'What's wrong with you?' I asked.

'Can I go now?'

He wasn't just surprised or frightened, he was in shock.

'Okay. But take this, will you?'

Kostya began grabbing the bottles and putting them in his pockets.

'Take a plastic bag, you dunce! What if there's someone in the hallway?'

The vampire obediently packed all the bottles into a plastic bag bearing the noble inscription: 'For the resurrection of Russian culture!' He gave the owl a sideways glance, went out into the hall and hastily began putting on his shoes.

'Call again,' I said. 'I'm not your enemy. Not until you cross that line, I'm not.'

He nodded and shot out of my apartment like a bullet. I shrugged and closed the door, then went back into the kitchen and looked at the owl.

'Well? What happened there?'

It was impossible to read anything in those amber-yellow eyes. I threw my hands up.

'How can we work together? Eh? How are we going to collaborate? Do you have any way of communicating? I'm trying to be frank with you, do you hear me? To have a frank conversation!'

I didn't go all the way into the Twilight, just reached in there with my thoughts. It's not good to trust anyone you don't know like that, but the boss wouldn't have given me a partner I couldn't trust, would he?

No answer. Even if Olga could communicate telepathically, she wasn't going to.

'What shall we do? We need to look for that girl. Will you accept her image?'

No reply. I sighed and tossed the scrap of my memory at the bird anyway.

The owl stretched its wings and soared across on to my shoulder.

'Ah, so we do hear when we're spoken to? But we don't condescend to reply. All right, have it your own way. What should I do?'

The owl still wouldn't speak.

In fact, I knew what to do. There was no hope of success, but that was a different matter.

'And how am I going to wander round the streets with you sitting on my shoulder?'

A mocking glance, definitely mocking. And the bird on my shoulder shifted into the Twilight.

So that was it. An invisible observer. And no ordinary observer – Kostya's reaction to the owl had been very instructive. Apparently I'd been given a partner that the powers of the Dark knew better than the rank-and-file servants of the Light did.

'Right,' I said cheerfully. 'I'll just grab a bite to eat, okay?'

I took out some yoghurt and poured a glass of orange juice. The very thought of what I'd been feeding myself with for the last week – half-raw steaks and meat juices that were not much different from blood – made me feel sick.

'Maybe you'd like a bit of meat?'

The owl turned away.

'Have it your own way,' I said. 'No doubt when you get hungry you'll find some way to communicate.'

CHAPTER 3

I LIKE WALKING round town inside the Twilight. You don't actually become invisible, or you'd have people bumping into you all the time. They just somehow look straight through you and don't notice you. But this time I'd have to work out in the open.

The day's not our time. Odd as it may seem, the followers of the Light work at night, when the Dark Ones become active. And just at the moment there wasn't so much the Dark Ones could do. During the day vampires, werewolves and Dark Magicians are obliged to live like ordinary people.

Most of them, that is.

I was walking round Tulskaya metro station. Following the boss's advice, I'd worked through all the stations on the circle line where the girl with the black vortex could possibly have left the metro. She should have left a trail behind, a weak one maybe, but still detectable. Now I'd decided to work my way out along the radial lines.

It's a stupid station in a stupid district. Two exits quite some distance apart. A market, that pompous-looking skyscraper occupied by the tax police, a massive apartment block. With all those dark emanations all around, any chance of picking up the trail of the black vortex was looking pretty doubtful.

Especially if it had never even been there.

I walked round everything, trying to sense the girl's aura, sometimes glancing into the Twilight at the invisible bird nesting on my shoulder. The own was dozing. It couldn't sense anything either, and for some reason I felt sure its reconnaissance skills were better than mine.

Once a militiaman checked my papers. Twice I was pestered by crazy blokes who wanted to give me, absolutely free – that is for only fifty roubles – a Chinese fan, a child's toy and a dirt-cheap Korean mobile phone.

And again I couldn't control myself. I brushed aside the next street salesman who pestered me and performed a remoralisation. Only a little one, right at the very edge of what's allowed. Maybe he would start looking for a different kind of work. Or maybe he wouldn't. . .

But just at that moment someone grabbed hold of my elbows. A second earlier there was no one there – then suddenly there was a young couple. An attractive-looking girl with red hair and a solid-looking man with a surly expression on his face.

'Stop there,' said the girl. She was the leader, I could tell that straight off. 'Day Watch.'

Light and Dark!

I shrugged and looked at them.

'Your name,' the girl demanded.

There was no point in lying, they'd captured the image of my aura already, and after that identifying the individual is only a matter of time.

'Anton Gorodetsky.'

They waited.

'Other,' I confessed. 'Night Watch agent.'

They lifted their hands off my elbows, and even took a step back. But they didn't seem disappointed.

'Okay, let's enter the Twilight,' said the man.

They didn't look like vampires. That was one good thing. At least I could hope for a certain degree of objectivity. I sighed and shifted from one reality into the other.

The first surprise was that they turned out to be genuinely young. A witch of about twenty-five and a warlock of about thirty, the same age as me. I thought that if I needed to, I could probably even recall their names, there weren't that many witches and warlocks born in the late 1960s.

The second surprise was that the owl wasn't there on my shoulder. Or rather, it was: I could feel its claws and I could see it, but only with some effort. It was as if the bird had shifted realities at the same time as I had and moved into a deeper level of the Twilight.

This was getting really interesting!

'Day Watch,' the girl repeated. 'Alisa Donnikova, Other.'

'Pyotr Nesterov, Other,' the man muttered.

'You have some kind of problem?'

The girl drilled me with one of those speciality 'witch's glances'. She started to look more attractive and appealing with every moment. Of course, I'm protected against direct influence, it's not possible to bewitch me, but it certainly looked impressive.

'We're not the ones with the problem. Anton Gorodetsky, you have entered into unsanctioned contact with a human.'

'Yes? And what was that?'

'Only a seventh-degree intervention,' the witch admitted reluctantly. 'But an offence is an offence. And you also urged him towards the Light.'

'Are we going to draw up a charge report?' I suddenly found the situation amusing. Seventh degree was next to nothing – a level of influence on the borderline between magic and ordinary conversation.

'We are.'

'And what are we going to write? A Night Watch agent slightly increased one human's aversion to deception?'

'Thereby disrupting the established balance,' the warlock barked out.

'Really? And what harm does it do to the Dark? If the guy stops working as a petty crook, his life is bound to get worse. He'll be more moral, but unhappier too. Under the terms of the commentaries on the Treaty on the balance of power, that's not regarded as a violation of the balance.'

'Sophistry,' the young woman said curtly. 'You're a Night Watch agent. What might be pardonable for an ordinary Other is not acceptable from you.'

She was right. It was still a violation, even if it was petty.

'He was obstructing me. I have a right to use magical intervention in the course of conducting an investigation.'

'Are you on duty, Anton?'

'Yes.'

'Why during the day?'