Like all connurb block flats it was surprisingly small, even with all the furniture removed: a lounge with a screened off kitchen, one master bedroom, a toilet-shower, and a secondary sleeping cubicle. The rooms were decorated in ancient wallpaper: the pattern a mixture of dirty yellow and green, faded with age. Picture frames had left shadows on the walls, keeping rectangles of wallpaper rich and vibrant. A faint dark line marking the top edges. The McEwens must have been a house-proud pair, because other than that, the whole place was scrupulously clean.

A faint rumble sounded from down the hall. The SOC team had started scanning.

Will wandered from tiny room to tiny room; amazed that anyone could live somewhere this small, let alone raise two kids here. Every apartment in Monstrosity Square was the same: a testament to the ingenuity and inhumanity of the planning department.

Compressed Urban Habitation they called it. Cram as many people into as small a space as possible, then sit back and wonder why they start killing themselves. And each other.

He checked his watch, gave the meagre flat one last look, then headed back out into the hallway, locking the door behind him.

As Will hurried up the corridor the floor started to tremble. By the time he’d reached Allan Brown’s flat the sonics were in full swing. He had to shout to be heard over the din in the kitchen.

‘HOW MUCH LONGER?’

Stein puffed out his cheeks. ‘DONE THE LOUNGE AND BEDROOM, BUT YOU KNOW HOW IT IS: SOMETIMES THE MACHINERY WORKS FIRST TIME, SOMETIMES WE HAVE TO KICK THE HELL OUT OF IT.’ He aimed a boot at the scanner’s dented canister. ‘AND IT’S ALWAYS US! I MEAN IT WOULD BE FAIR ENOUGH IF IT WAS SOMEONE ELSE’S TURN NOW AND AGAIN, BUT FOR GOD’S SAKE: EVERY SODDIN’ TIME?’

Thankfully the howling scanning booms meant that Will could only catch snatches of the rant. He nodded in sympathy and when the subsonics kicked in mimed his concern and buggered off through to the main bedroom.

It was slightly quieter in here, but not by much, even with the door shut. DS Cameron and Sergeant Nairn were picking through the mounds of rubbish. A transparent evidence sack sat in the middle of the cluttered bed-there wasn’t much in it.

‘ANY LUCK?’

DS Cameron squinted at him. Then cupped a hand over her ear. ‘WHAT?’

‘HAVE YOU HAD ANY LUCK?’

‘A BIT. WHAT ABOUT YOU?’

‘WASTE OF TIME. THE MCEWENS’ PLACE IS CLEAN AS A WHISTLE, READY FOR THE NEXT POOR SODS TO MOVE IN. NOTHING LEFT.’

‘SORRY, CAN’T HEAR A THING OVER THAT BLOODY-’ The scanners fell silent and DS Cameron paused for a moment, then sighed. ‘God, that’s better…What were you saying?’

But Will was heading back to the kitchen: the scanners still had another cycle to go. If they were quiet now it meant they weren’t working. He burst into the room to see Stein and Beaton on their knees, poking at the equipment.

‘What’s wrong with it?’

Beaton jiggled one of the leads. ‘It’s buggered: that’s what’s wrong with it.’

Will checked his watch again. They’d been here almost fifteen minutes. Give it another six or seven to get back to the roof. Twenty-two minutes. Even then that was probably going to be tight. Running at full tilt the scanners would have interfered with all electronic activity within six hundred feet: that included the public virtual reality channels. Robbed of the only real escape they had, the locals would start looking for something else to fill the gap. Religion might have been the opium of the masses, but VR was their crack cocaine.

And no one liked going cold turkey.

‘How long to fix it?’

‘Don’t know.’ Beaton looked up at her colleague who gave a shrug. ‘Five, maybe ten minutes?’

That made it over half an hour. Will shook his head-there was a difference between reasonable risk and reckless stupidity. ‘You’ve got two.’

‘No chance. We’ve got to recalibrate the whole array or it’ll just fall over again.’

‘Then pack it up. We’re leaving.’

Stein shook his head and smiled as if he was talking to a small child. ‘You don’t understand-’

‘If you two aren’t ready to go by the time I count to ten, we’re leaving you behind. You can take your chances with the natives.’

‘But we-’

‘One. Two. Three-’

‘But,’ Stein pointed at the machinery’s dented casing. ‘The subsonics-’

‘Five. Six-’

‘We’ve got to recalibrate, or-’

‘Eight. Nine-’

‘But-’ He was beginning to go red in the face.

‘Ten. Time’s up.’ Will turned and shouted into the bedroom, ‘Sergeant Nairn, get your team together. We’re pulling out.’

‘Yes, sir!’ Nairn emerged from the bedroom with an evidence bag slung over his shoulder. DS Cameron was carrying one too, lurching after the sergeant into the lounge. With fifteen severed heads stuffed into the transparent sack, she looked like a macabre Santa Clause.

‘Did we get a VR set?’

‘Nairn’s got it,’ she said, as the man in question marched out the front door. ‘All twisted up into a pretty little shrine decorated with finger bones and jelly babies.’

Will closed his eyes. Blood and drums in the darkness. Definitely time to go.

‘Come on then.’ He ushered her out into the corridor.

A muffled, rapid conversation erupted in the apartment behind them: Beaton and Stein arguing over whether or not they’d really be left behind. Then there was the sound of mechanical scrabbling and professional swearing. The SOC team tumbled out of the flat, forcing their battered equipment back into its casing as they went.

‘All right, all right! We’re coming.’

Will reached up and keyed his throat-mike. ‘Lieutenant Brand, this is Hunter: prepare for dust-off.’

‘Roger that, Hunter. We are hot to trot.’

‘You see,’ said Detective Sergeant Cameron, hoisting her evidence bag, ‘nothing to worry about. I told you this place isn’t half as bad as you think.’

And that was when the shooting started.

It started out as a faint crack, like the sound an ice cube makes dropped into warm water. Then another. And another. Then the sound changed, grew deeper, got closer. Gunfire echoed down from the floors above, and Rhodes’ voice crackled in Will’s earpiece:

‘…repeat, we have hostiles!’

No: this wasn’t fair! He’d been careful. They were heading home!

Sergeant Nairn punched up the power on his Thrummer and shouted: ‘Dickson, Wright, get your arses back here on the double!’

They all sprinted for the broken escalator. Nairn jumped onto the ramp, his Thrummer searching for targets. ‘Talk to me Rhodes, what the hell’s going on up there?’

‘…Fifteen, maybe more. Automatic projectile weapons; I think I see a Zinger.’ The harsh burr of a Thrummer tore through the air. ‘Orders?’

Nairn looked at Will and waited.

‘We…It…’

‘Sir, I hate to hassle you, but now would be a good fucking time.’

‘But we…’ Deep breath. In through the nose, out through the mouth.

‘Fine.’ Nairn hit his throat mike again. ‘Rhodes, you are cleared for deadly force. I want everything neutralized and-’

‘No!’ Will grabbed the sergeant’s arm. ‘We’ve had two cases of VR syndrome on this floor in one week, probably hundreds more we don’t know about. You have to keep any contact to a minimum or this whole place will explode.’

‘Oh Jesus…’ Nairn swallowed, hard. ‘Rhodes-disregard last order, non-lethal force only.’

‘Sarge? Have you gone off your fuckin’-’

‘Shut up and do what you’re told. People: we need dust-off and we need it now!’ He charged up the ramp, with privates Dickson and Wright hurrying after him, leaving Will, DS Cameron and the SOC team behind.

Angry noises filtered up from the floors below: it didn’t matter that the scanners had been turned off and packed way, it would take time for the building’s local network to reboot. Sherman House was suffering from VR withdrawal. And if the residents couldn’t have computer-generated death and destruction, they could always have the real thing.