The man cracked his knuckles and advanced. 'You fuckin' deaf? I told you: let the bitch go!'

Sighing, Logan dug out his wallet and flipped it open, exposing his warrant card. 'Detective Sergeant Logan McRae.

Still want to break my head open?' The man froze, looked from Logan's ID to Logan to the struggling girl and back at Logan aga n. Then legged it.

Logan i nd the girl watched him disappear – for a big man he moved pretty fast. She stood open-mouthed, forgetting to struggle, before hurling a string of foreign-language abuse after her scarpering pimp. Logan had no idea what the words meant, but the general gist was clear enough.

'Well,' he said, when she'd run out of breath and inspiration, 'it's OK: I'm not going to arrest you. I really do just want to talk.'

She looked him up and down again. 'I talk very good dirty.

You want talk dirty?'

'Not that kind of talking. Come on, I'll buy you a drink.'

The Regents Arms was a little bar on Regent Quay with a three am licence. Not the smartest place in Aberdeen: it was dark, dirty, missing an apostrophe, and smelled of spilt beer and old cigarettes. Popular with the kind of people that hung around the docks after sundown. Logan took one look at the clientele and spotted at least three he'd arrested before – bit of aggravated assault, bit of prostitution, bit of breaking and entering – so there was no way he was going to risk using the toilets here. Wander into a small room with only one exit and a bar full of people who'd love to see a policeman with his brains leaking out onto the dirty floor? Might as well smash himself in the face with a claw hammer, save everyone the bother. But no one said anything as he sat the young girl down in a booth and bought her a bottle of Bud. If she was old enough to be selling her body on the streets, she was old enough for a beer.

'So,' he said, 'who was your friend?'

She scowled and hurled another barrage of incomprehensible abuse at her absent protector. When Logan asked what language she was swearing in she told him: 'Lithuanian.' Her name was Kylie Smith – likely bloody story thought Logan – and she'd been in Scotland for almost eight months now.

First Edinburgh then Aberdeen. She preferred Edinburgh, but what could she do? She had to go where she was sent.

And no she wasn't sixteen, she was nineteen. Logan didn't buy that one either. The pub's lighting was murky, but it was still better than the flickering yellow streetlights in Shore Lane. She was fourteen if she was a day. Like it or not, she'd have to go to the station after this. There was no way he could turn a child that age back out onto the streets. She should still be in school!

Her 'friend' had told her to call him Steve, but Logan wasn't to cause trouble for him, because she had to stay with him, and he'd beat her. Logan just made noncommittal noises and asked Kylie where she'd been yesterday night.

'I go with man in suit, he want I do dirty thing, but he pay good. Then I go with other man, smell very bad of chips, skin is all grease. I go with-'

'Sorry, that's not what I meant.' Logan tried not to think of oily fingers pawing away at the schoolgirl. 'What I meant was: where were you getting picked up from?'

'Oh, I understand. Same place today. All night. I make good money.' She nodded. 'Steve bring me breakfast, I do so good. Happy Meal.'

Last of the big spenders. 'Did you know a girl was attacked last night?'

She nodded again. 'I know.'

'Did you see anything?'

Kylie shook her head. 'She stand there all night, only one man come make fuck with her.'

'What did he look like?'

'It very dark…' A frown and then, 'White hair all spike?'

She stuck her hands to the side of her head, fingers pointing upwards. 'You know? And beard.' More hand gestures: this time the left, fingers bunched, right on the point of her chin.

'He smell of chips too.'

Logan sat back and smiled. That would be Jamie McKinnon, no doubt fresh from robbing another late-night fast-food joint.

Goodbye alibi.

'Did you hear anything they said?'

She shook her head and finished her bottle of beer. 'I go with other man.'

Logan sat back in his seat and looked at her. 'You know someone killed her?'

Kylie sighed, her face suddenly much older than its years.

She knew. People got hurt all the time. People died. It was the way the world worked.

'Would you come with me to the station? Look at some photographs? Make a statement? Just what you've told me?'

She shook her head. 'Steve angry if I not making money.'

She rolled up the sleeve of her low-cut blouse, showing him the cluster of cigarette burns in the crook of her elbow.

There were needle tracks in amongst the circular scars, just enough to get addiction underway. To make her dependent on 'Steve'.

'What if I told you I could make sure Steve never hurt you ever again?'

Kylie just laughed. That was crazy talk. She wasn't going to come with him, she wasn't going to police station, she wasn't going to cause no trouble for Steve. Thank you for beer and goodbye. Logan insisted, but Kylie was having none of it. She jumped to her feet and made a run for the door.

Logan leapt up to follow, and that was when things started to go wrong. A large man with a tattoo the size of a Rottweiler blocked the exit, just after Kylie charged through the door.

He was a good foot shorter than Logan was, but more than made up for it in breadth.

Logan screeched to a halt.

'Lady's no' wantin' your company,' he said, his accent broad Peterhead.

'Look, I need to catch her! She's only fourteen!'

'Oh, like 'em young do you?' Through gritted teeth.

'What? No! I'm a police officer! She…' And that's when Logan heard it: the silence. Every conversation in the pub had come to a sudden halt. The only sound in the place was a tatty-looking bandit, bleeping and pinging away to itself.

Fuck…

'OK,' he turned around and addressed the bar as a whole, 'I'm looking for whoever killed Rosie Williams last night. I don't want to cause trouble for anyone else.' More silence.

Cold sweat was beginning to run down Logan's back. 'Some bastard beat Rosie to death: strangled her, smashed her face in, broke her ribs. She drowned in her own blood!'

Logan turned to face the tattooed thug blocking the door.

'She deserved better than that. Everyone does.'

He was going to get his arse kicked. He could feel it.

The wee muscleman frowned in concentration. The silence stretched. And then he said, 'Go on, bugger off.' He jerked a thumb over his shoulder. 'Mind this, though: it's no' healthy for you in here. Don't come back.'

By the time he was outside there was no sign of Kylie.

Logan didn't know any Lithuanian, so he swore in good old-fashioned Scottish.