Watson shrugged. 'Dunno, sir. Maybe it's some sort of obsessive compulsive disorder?' She paused, brow furrowed in thought. 'Or maybe he's just a big fat b.a.s.t.a.r.d.'

Logan didn't know whether to laugh or look shocked.

'Tell you one thing though, sir, he's a d.a.m.n good policeman. And you don't f.u.c.k with him twice.'

Somehow Logan had already come to that conclusion all on his own.

'Right.' He stopped at the front door. The hallway was festooned with photographs, just like the lounge. 'Get that picture down to the nearest newsagents. We'll need about a hundred photocopies and-'

'The local boys have already done it, sir. They've got four officers going door to door all along the route Richard would have taken to the shops, handing them out.'

Logan was impressed. 'They don't hang about.'

'No, sir.'

'OK, let's get half a dozen uniform down here to give them a hand.' He pulled out his mobile phone and started dialling, his finger freezing over the last number. 'Oh, ho ...'

'Sir?'

A flash-looking motor had pulled up at the kerb and out bustled a familiar, short figure, all wrapped up in a black overcoat, wrestling with a matching umbrella.

'Looks like the vultures are circling already.'

Logan grabbed a brolly from the hallway and stepped out into the rain. The icy water thrummed off the umbrella as he stood and waited for Colin Miller to climb the stairs.

'Sergeant!' said Miller, smiling. 'Long time no see! You still carting that tasty...' The smile became even broader as he saw WPC Watson scowling from the doorway. 'Constable! We was just talking about you!'

'What do you want?' Her voice was even colder than the grey afternoon.

'Business before pleasure, eh?' Miller dug a fancy dictaphone out of his pocket and pointed it at them. 'You've got another missing kid. Are you-'

Logan frowned. 'How did you know another child's gone missing?'

Miller pointed out at the rain-soaked road. 'You've got patrol cars out broadcastin' the kid's description! How do you think I found out?'

Logan tried not to look as embarra.s.sed as he felt.

Miller winked. 'Ah, don't worry about it. I make an a.r.s.e of myself all the time, but.' He held the dictaphone up again. 'Now, is this disappearance connected to the recent discovery of-'

'We have no comment to make at this time.'

'Oh, come on!'

Behind Miller another car had pulled up, this one with the BBC Scotland logo emblazoned down the side. The media were going to have a field day. Yesterday a little boy turned up dead, today another one had gone missing. They'd all be jumping to the same conclusion as Miller. He could see the headlines now: 'HAS PAEDOPHILE KILLER STRUCK AGAIN?' The Chief Constable would have a fit.

Miller turned to see what Logan was staring at and froze. 'How about if-'

'I'm sorry, Mr Miller. I can't give you any further details at this time. You'll just have to wait for the official statement.'

He didn't have to wait long. Five minutes later DI Insch's mud-splattered Range Rover pulled up. By then a little cordon of newspaper and television people had appeared, forming a wall of microphones and lenses at the foot of the steps, huddling beneath large black umbrellas. Just like a funeral.

Insch didn't bother getting out of his car, just wound down his window and waved Logan over. The cameras turned to watch Logan cross the road and stand in the rain beneath his borrowed umbrella by DI Insch's window, trying not to wince at the smell of wet spaniel that oozed out of the car's interior.

'Aye, aye,' said the inspector, nodding towards the ring of cameras. 'Looks like we're going to be on the telly tonight.' He ran a hand over his bald head. 'Good job I remembered to wash my hair.'

Logan forced a smile. The scars crisscrossing his stomach were starting to bother him as last night's punch in the guts made its presence felt.

'Right,' said Insch. 'I've been authorized to release a statement to the media. Before I do, is there anything I need to know that's going to make me look like an a.r.s.e here?'

Logan shrugged. 'Far as we can tell the mother's being straight with us.'

'But?'

'Don't know. The mother treats the kid like he's made of gla.s.s. Doesn't get out on his own. All his toys are for a kid two years younger than he is. I get the feeling she's smothering the life out of him.'

Insch raised an eyebrow, causing the pink, hairless skin of his head to wrinkle. He didn't speak.

'I'm not saying he hasn't been s.n.a.t.c.hed.' Logan shrugged. 'But still...'

'Point taken,' said Insch, smoothing himself down. Unlike the filthy, smelly Range Rover he was immaculately turned out in his best suit and tie. 'But if we play this down, and he turns up all strangled with his w.i.l.l.y cut off, we'll be up to our ears in s.h.i.te.'

Logan's phone went off in an explosion of beeps and whistles. It was the Queen Street station. They'd picked up Duncan Nicholson.

'What... ? No.' Logan smiled, the phone clamped to his ear. 'No, stick him in a detention room. Leave him there to sweat till I get there.'

By the time Logan and WPC Watson got back to Force Headquarters a full-blown search was underway. DI Insch had more than trebled the six uniforms Logan had drafted in to help and now more than forty police men and women, four dog-handlers and their alsatians, were out in the freezing rain, searching every garden, public building, shed, bush and ditch between Richard Erskine's home and the shops on Victoria Road.

The desk sergeant told them that Duncan Nicholson had been stuck in the mankiest detention room in the place. He'd been there for nearly an hour.

Just to be on the safe side, Logan and WPC Watson stopped off at the canteen for a cup of tea and a bowl of soup. Lingering over the pea and ham while Nicholson sat in a room, all alone, and worried.

'Right,' said Logan, when they'd finished. 'How'd you like to drag Mr Nicholson into an interview room? Give him the silent glower routine? I'll check up on the search and pop along in about, fifteen, twenty minutes. He should be bricking it by then.'

Watson stood, cast one last longing look at the thick slices of sponge pudding and steaming yellow custard, and headed off to make Duncan Nicholson's life even more miserable.

Logan got an update from the admin officer in the incident room: the search teams hadn't turned up anything and neither had the door-to-door interviews. So Logan grabbed a cup of tea from the machine in the hallway and drank it slowly, filling in the time. Then took another painkiller. When twenty minutes had elapsed he headed down to interview room two.

It was small and utilitarian, done up in a nasty shade of beige. Duncan Nicholson sat at the table, opposite a silent, scowling, WPC Watson. He was looking very uncomfortable.

The room was no smoking and Nicholson obviously had a problem with that. There was a pile of shredded paper on the table in front of him and as Logan entered Nicholson jumped, sending little sc.r.a.ps of white fluttering to the scuffed blue carpet.

'Mr Nicholson,' said Logan, sinking down into the brown plastic chair next to Watson. 'Sorry to keep you waiting.'

Nicholson shifted in his chair, little beads of sweat sparkling on his upper lip. He wasn't a day over thirty-two, but looked closer to forty-five. The hair on top of his head was shaved down to the bone, blue-grey stubble showing between shiny patches of pink scalp. Each of his ears had been pierced in at least three places. The rest of him looked as if it had been thrown together on a Monday morning before the factory was properly awake.

'I've been here for hours!' he said, mustering up as much indignity as he could. 'Hours! There was nae bog! I wis burstin'!'

Logan frowned. 'Dear, dear, dear. There's obviously been some mistake, Mr Nicholson. You came forward of your own free will, didn't you? No toilet? I'll have a word with the duty sergeant. Make sure it doesn't happen again.' He smiled a disarming, friendly smile. 'But we're all here now, so shall we get started?'

Nicholson nodded, smiling a little, feeling rea.s.sured. Feeling better.

'Constable, would you do the honours?' Logan pa.s.sed Watson two brand new audiotapes and she unwrapped them, sticking one in each side of the recorder bolted to the wall before doing the same with a pair of videotapes. The machine clicked and bleeped as she pressed 'RECORD'.

'Interview with Mr Duncan Nicholson,' she said, going through the standard names, date and time.

Logan smiled again. 'Now then, Mr Nicholson, or can I call you Duncan?'

The man on the other side of the table cast a nervous glance at the camera in the corner of the room, over Logan's shoulder. At last he nodded his shaved head.

'So, Duncan, you found the body of David Reid last night?'

Nicholson nodded again.

'You have to say something, Duncan,' said Logan, his smile getting wider by the minute. 'The tape can't hear you if you nod.'

Nicholson's eyes darted back to the staring gla.s.s eye of the video camera. 'Er... Oh, sorry. Yeah. Yeah, I did. I found him last night.'

'What were you doing down there in the middle of the night, Duncan?'

He shrugged. 'I wis... takin' a walk. You know, had a row with the wife and went for a walk.'

'Down the riverbank? In the dead of night?'

The smile started to fade. 'Er, yeah. I go down there sometimes to, you know, think an' stuff.'

Logan crossed his arms, mirroring the PC sitting next to him. 'So you went down there to think. And just happened to fall over the murdered body of a three-year-old boy?'

'Er, yeah... I just... Look, I...'

'Just happened to fall over the murdered body of a three-year-old boy. In a waterlogged ditch. Hidden beneath a sheet of chipboard. In the dark. In the pouring rain.'

Nicholson opened his mouth once or twice, but nothing came out.

Logan left him sitting in silence for almost two minutes. The man was getting more and more fidgety by the second, his shaved head now as sweaty as his upper lip, the smell of second-hand garlic oozing out of him in nervous waves.

'I'd been... drinking, OK? I fell down, nearly killed myself goin' down that b.l.o.o.d.y bank.'

'You fell down the bank, in the pouring rain, and yet when the police arrived there wasn't a speck of mud on you! You were clean as a whistle, Duncan. That doesn't sound like someone who's just fallen down a muddy bank and into a ditch, now does it?'

Nicholson ran a hand over the top of his head, the stubble making a faint scritching noise in the oppressive interview room. Dark blue stains marked his armpits.

'I... I went home to call you. I got changed.'

'I see.' Logan switched the smile back on again. 'Where were you on the thirteenth of August this year, between half past two and three in the afternoon?'

'I... I don't know.'

'Then where were you between the hours of ten and eleven this morning?'

Nicholson's eyes snapped open wide. 'This mornin'? What's goin' on? I didnae kill anyone!'

'Who said you did?' Logan turned in his seat. 'Constable Watson, did you hear me accuse Mr Nicholson of murder?'

'No, sir.'

Nicholson squirmed.

Logan produced a list of all the children registered missing in the last three years and placed it on the table between them.

'Where were you this morning, Duncan?'

'I was watching the telly.'

'And where were you on,' Logan leant forward and read off the list, 'the fifteenth of March between six and seven? No? How about the twenty-seventh of May, half-four to eight?'

They went through every date on the list, Nicholson sweating and murmuring his answers. He wasn't anywhere he said. He was at home. He was watching television. The only people who could vouch for his whereabouts were Jerry Springer and Oprah Winfrey. And they were mostly repeats.

'Well, Duncan,' said Logan when they'd got to the end of the list, 'doesn't look too good, does it?'

'I didn't touch those kids!'

Logan sat back and tried DI Insch's silent treatment again.

'I didn't! I f.u.c.kin' came to you lot when I found that kid, didn't I? Why the h.e.l.l would I do that if I killed him? I wouldn't kill a kid: I love kids!'

WPC Watson raised an eyebrow and Nicholson scowled.

'Not like that! I've got nephews and nieces, OK? I wouldn't f.u.c.kin' do something like that.'

'Then let's go back to the start.' Logan shoogled his chair in closer to the table. 'What were you doing wandering about on the banks of the Don in the middle of the night in the pouring rain?'

'I told you I was p.i.s.sed...'

'Why don't I believe you, Duncan? Why do I get the feeling that when the report comes back from Forensics there's going to be evidence linking you to the dead boy?'

'I didn't do anything!' Nicholson slammed his hand down on the tabletop, making the little pile of shredded paper scatter and fall like snow.

'We've got you, Mr Nicholson. You're only kidding yourself if you think you're going to talk your way out of it. I think a little time in the cells is going to do you the world of good. We'll talk again when you're ready to start telling the truth. Interview terminated at thirteen twenty-six.'

He got WPC Watson to escort Nicholson down to the cellblock, hanging on in the interview room until she returned.

'What do you think?' he asked.

'I don't think he did it. He's not the right type. Not smart enough to lie convincingly.'

'True.' Logan nodded. 'But he's lying all the same. No way he was down there having a bit of a late night stagger. You get plastered, you don't go stomping about down the riverbank in the p.i.s.sing rain for a laugh. He was down there for a reason, we just don't know what it is yet.'

Aberdeen harbour slid by the car window, grey and miserable. A handful of offsh.o.r.e supply vessels were tied up along the docks, their cheery yellow-and-orange paintwork dulled by the pouring rain. Lights glinted in the semi-darkness of the afternoon as containers were winched off lorries and onto the waiting boats.