He froze for a moment, then realised that it was probably the wind playing with the letterbox flap. Outside, through the top, unfrosted panel of his bathroom window, he could see the tip of the solitary withered and miserable-looking inner-city poplar that grew outside the back of next door’s house, uplit by the amber glow of street lights, swaying gently.

He watched it gently undulating from side to side, and listened to the pleasing tinkle of a wind chime.

He left the TV muted. Not that he was the twitchy sort, but there had been several burglaries along their cul-de-sac in recent months. In any case, it was relaxing listening to the hiss of a breeze through the leaves, and the gentle random musical notes. Despite being so central in London, and so close to the high street, he was constantly amazed at how quiet their little piece of backstreet Notting Hill was. In the distance a police siren wailed and a dog barked in reply . . . but other than that, so peaceful.

Another noise.

It sounded like the slightest scrape of one of his kitchen stools across the parquet floor. That was all it was . . . a nudge. Not a sound that could be mistaken for the central heating coming on, or any of the other plethora of tickings and creakings a house will make in the night.

It was the sound of someone else in his house.

Shit.

He felt the first cold prickle of anxiety, and a quickening of his breath. He reached out and took a pull on his inhaler.

Just a kid . . . a chav looking for something easy to swipe and run.

He knew from past dealings with young offenders that they were at least as frightened as the people they robbed or mugged. If there was someone down there, a confident boo would have him running like a startled rabbit.

‘YOU HAVE EXACTLY TEN SECONDS TO PISS OFF BEFORE I CALL THE POLICE!’ His voice boomed out of the bathroom. He listened intently for the sound of trainers skidding on his waxed floor, the clatter and slam of a door or window being opened and the diminishing slap of running feet outside on the pavement.

But he heard nothing.

‘ALL RIGHT, SCREW IT. I’M CALLING NOW,’ he bellowed again. This time there was a wheezy signature to his baritone voice.

He picked up his cordless, dialled all the nines, held it to his ear waiting to hear the trill of the call ringing through. But there was nothing, just a rustle and crackling and then something that sounded very much like a breath being taken.

‘I can hear you up there,’ a voice muttered out of the earpiece.

‘Whuh?!’ he blurted, dropping the phone onto his wet belly.

He heard footsteps across the downstairs hall.

‘What do you want?’ Tom called out, his troubled breathing beginning to rob his voice of its natural authority.

The lights upstairs suddenly went out, leaving the bathroom illuminated only by the flickering glow of his plasma screen. Some light spilled up the stairs from the kitchen and hallway lights, and he thought he caught the momentary fluttering of a shadow cast up the stairway and onto the wall outside his bathroom. Then it darted out of sight.

Oh fuck, fuck, fuck.

The lights downstairs went out. And finally his TV winked off.

‘Please! Take what you want and go!!’ he gasped in the darkness, his eyes struggling to adjust.

He heard the creak of weight settling on one of the stairs.

Oh God, oh fuck.

‘Look,’ he puffed between laboured breaths, ‘my wallet is in my jacket down in the kitchen. There’s at least a couple of hundred pounds in there.’

No reply.

‘There’s a cash card in there too,’ he said and sucked quickly from his inhaler. ‘The PIN is one, four, six, six.’

He heard creaking again on the stairs and knew that was the other wonky step near the top.

‘Please! Take what you want and go!’

His eyes began to pick out some details around him, lit by the diffused amber glow of the street light outside.

‘I’ve come to kill you, Tom,’ a voice whispered from just outside his open bathroom door.

‘Who are you?’ Tom replied.

‘Not that important who I am now, is it?’

He pulled himself with some difficulty up out of the warm, soapy water.

‘Stay in the bath!’

‘O-Okay.’

Play along, Tom. Play along.

He desperately searched his memory for someone who might have a reason to come after him like this. He’d contributed to the arrest and conviction of perhaps a dozen murderers in some small way. But he couldn’t imagine how they could have—

‘I’m afraid you know a little too much about things right now.’

‘W-what? I . . . I know what?’

‘Sorry, I’m not here to discuss that. I’m here to kill you.’

‘What? P-please . . . I have money . . .’ he stammered, struggling with difficulty to find his breath. ‘If you t-tell me how much—’

Then his eyes detected something shifting. It was low down, squat, in the doorway, swaying from side to side. A rocking movement - compulsive. Tom trawled his memory for the most likely criminally insane candidates. There were one or two over the years whom he had written notes on, interviewed, but not necessarily been instrumental in putting away. No revenge motive he could think of.

‘What’s your worst fear?’ the voice whispered.

‘My . . . my worst . . . why? What? Why are you—’

‘Come on. What do you fear the most?’

‘I . . . p-please . . . don’t—’

‘Let me guess, then.’

Tom felt his lungs clench like a fist and a wave of light-headedness caused him to sway. He sat down heavily in the bath. Water splashed noisily out of the tub and onto the floor.

‘I hear you wheezing,’ whispered the voice. ‘You’re asthmatic, aren’t you?’

Tom refused to answer.

‘Hmm, I had a cousin who was. Worst thing she feared was suffocating. She used to have nightmares about that, night after night, screaming . . . gasping.’

‘Oh God, please no!’ he pleaded, subconsciously fumbling in the dark for his inhaler.

The voice laughed. A dry, brittle rattle that sounded sly and childlike.

‘So, I’m afraid that’s how it has to be, Dr Thomas Griffith.’

Oh God Oh God Oh God.

‘This can be very quick. I’ve done it a few times before.’ The voice laughed softly. ‘They call it water-boarding . . . sounds like something fun, doesn’t it?’

‘Please, not drowning! Please!’

‘Shhh. Listen, I can make it easy for you. I’ll hold you under while you breathe in that water. Thirty seconds of thrashing and it’s over. The longer you hold your breath, the more your body will fight it.’

‘Oh fuck n-no!’

‘Or I guess you can struggle . . . and this’ll take us both a lot longer. It’ll be harder on you.’

Tom pulled himself unsteadily up onto his knees in the bath and suddenly felt his bowels open wide. Above the roar of blood in his ears and the deafening rasp of air struggling through a pinhole gap in his throat, he heard the tumbling of his own shit into the bath water.

‘Decision time. Do I have to wrestle you under? Or are you going to lie down like a good man?’

Tom’s vision clouded and the world skewed sideways.

He toppled over into the water, banging his head against the porcelain. He felt the impact and saw stars. Warm water rolled over his face and he snorted as water ran up his nose. Dazed and light-headed, he was still lucid enough to instinctively pull himself back out of the water.

He suddenly felt a heavy weight on his broad chest, holding him under. Through the turbulent, swirling veil of bath water, as his arms and legs scissored desperately, he thought he could just make out the pale face of his killer.

He nodded with satisfaction. There would be little noticeable bruising on the man’s body; he’d been careful not to hold him down under the water with his hands around the neck - instead he’d applied the weight of his body across the chest - no telltale thumb or finger marks.

He’d been taught by the best.

He fumbled in the water for the man’s inhaler, fished it out and then held down the dispenser button, listening to the rush of medication whistling out. It took a solid minute before the thing exhausted itself. He then tossed it casually on the floor of the bathroom.

Make it look natural.

He went downstairs, flipped all the fuses back on and returned to the bathroom. He studied the scene with the bright bathroom spotlights on; the pools of water that had splashed out of the tub, the dark clot of blood on the edge of the bath, the empty inhaler tossed angrily aside. He was looking at the scene of an overweight and unhealthy man who’d had an asthma attack, found his medication had run out, panicked getting out of the bath, slipped, fell, hit his head and drowned.

He smiled.

Good enough.

The British police were amateur enough to read this as an unhappy accident. He doubted whether the two murders would be linked anytime soon. If some bright young go-getter in the CID intelligence office did eventually get round to noticing they both shared an acquaintance by the name of Julian Cooke, it would be too late to haul him in for questioning, because Mr Cooke was about to become a statistic; another poor, unfortunate, ill-prepared trekker who had vanished in the wilderness of the Sierra Nevadas.

He unmuted the TV, recessed expensively in the granite wall. A news programme was on. He stopped for a few seconds to watch, intrigued by how differently news appeared to be presented and packaged here in the UK.

The British like their presenters ugly and old.

He was bemused by that, contrasting the pair of presenters on screen with the tanned and well-groomed young studio-brats he was used to watching back home.

Interesting.

He wandered downstairs, checking that he’d left no telltale signs of intrusion, then went back through the lounge into the kitchen, to the window he’d eased open, out into the yard, over a fence and was gone into the night.