Dariat had to grab at his seat as the carriage braked sharply. Tatiana gasped as she clung to one of the vertical poles, hanging on frantically as the lights began to dim.

“What’s happening?” she asked.

The carriage juddered to a halt. The lights went out, then slowly returned as the vehicle’s backup electron matrix came on line.

Rubra?

Little bastards are smashing up the station you were heading for. They’ve cut the power to the magnetic rail, I haven’t even got the reserve circuits.

Dariat hooked into the neural strata’s observation routines to survey the damage. The starscraper station was a scene of violent devastation. Smouldering lumps of polyp were chiselled out of the tunnel by invisible surges of energy; the guidance rail writhed and flexed, screaming shrilly as its movements yanked its own fixing pins out of the floor; severed electrical cables swung from broken conduits overhead, spitting sparks. Laughter and catcalls rang out over the noise of the violence.

A rapid flick through other stations showed him how widespread the destruction was.

Bloody hell.

Damn right,rubra said. She’s overdosing on the fury routine, but she’s playing smart with it.

A schematic of the tube network appeared in Dariat’s mind. Look, there are plenty of alternative routes left up to the spindle.

Yes, right now there are. But you’ll have to go back two stations before I can switch you to another tunnel. I can’t restore power to the rail in your tunnel, they’ve fucked the relays. The carriage will have to make it there on its own power reserve. You’d almost be quicker walking. And by the time you get there, the possessed will have wrecked a whole lot more stations. Bonney’s thought this out well; the way she’s isolating each stretch of tunnel will break up the entire network in another forty minutes.

So how the hell do we get to the spindle now?

Forwards. Go up to the station and walk though it. I can bring another carriage to the tunnel on the other side; that’ll get you directly up to the endcap.

Walk through? You’re kidding.

There’s only a couple of possessed left to guard each station after they’ve had their rampage. Two won’t be a problem.

All right, do it.

The lights dipped again as the carriage slid forwards slowly.

“Well?” Tatiana asked.

Dariat began to explain.

Starscrapers formed the major nodes in the habitat’s tube network; each of them had seven stations ringing the lobby, enabling the carriages to reach any part of the interior. Individual stations were identical; chambers with a double-arch ceiling and a central platform twenty metres long which served two tubes. The polyp walls were a light powder-blue, with strips of electrophorescent cells running the entire length above the rails. There were stairs at each end of the platform, one set leading up to the starscraper lobby, the other an emergency exit to the parkland.

In the station ahead of Dariat, the possessed finished their wrecking spree and went off up the stairs to start searching the starscraper. As Rubra predicted, they left two of their number behind to watch over the four tunnel entrances. Smoke from the attack was layering the air. Flames were still licking around the big piles of ragged polyp slabs blocking the end of each tunnel. Several hologram adverts flashed on and off overhead; an already damaged projector suffering from the proximity of the possessed turned the images to a nonsense splash of colours.

Given that the fire was dying away naturally, the two possessed were somewhat bemused when, seven minutes after everyone else left, the station’s sprinklers suddenly came on.

Dariat was three hundred metres down the tube tunnel, helping Tatiana out of the carriage’s front emergency hatch. The tunnel had only the faintest illumination, a weak blue glow coming from a couple of narrow electrophorescent strips on the walls. It curved away gently ahead of him, putting enough solid polyp between him and the station to prevent the two possessed from perceiving him.

Tatiana jumped down the last half metre and steadied herself.

“Ready?” Dariat asked. He was already using the habitat’s sensitive cells to study the pile of polyp they would have to climb over to get into the station. It didn’t look too difficult, there was an easy metre and a half gap at the top.

“Ready.”

Let’s go,dariat said.

The two possessed guards had given up any attempt to shield themselves from the torrent of water falling from the sprinklers. They were retreating back to the shelter of the stairs. Their clothes had turned to sturdy anoraks, streaked with glistening runnels. Every surface was slick with water now: walls, platform, floor, the piles of polyp.

Rubra overrode the circuit breakers governing the cables which powered the tube, then shunted thirteen thousand volts back into the induction rail. It was the absolute limit for the habitat’s integral organic conductors, and three times the amount the carriages used. The broken guide rail jumped about as it had while it was being tormented by the possessed. Blinding white light leapt out of the magnetic couplings as it split open. It was as though someone had fired a fusion drive into the station. Water droplets spraying out of the overhead nozzles fluoresced violet, and vaporized. Metal surfaces erupted into wailing jets of sparks.

At the heart of the glaring bedlam, two bodies ignited, flaring even brighter than the seething air.

It wasn’t just the one station, that would have drawn Bonney’s attention like a combat wasp’s targeting sensor. Rubra launched dozens of attacks simultaneously. Most of them were electrical, but there were also mass charges of servitor animals, as well as mechanoids switched back on, slashing around indiscriminately with laser welders and fission blades as energistic interference crashed their processors.

Reports of the tumult poured into the starscraper lobby where Bonney had set up her field headquarters. Her deputies shouted warnings into the powerful walkie-talkies they used to keep in contact with each other.

As soon as the blaze of white light shone down the tunnel, Dariat started to run towards it. He kept hold of Tatiana’s hand, pulling her onwards. A loud caterwaul reverberated along the tunnel.

“What’s Rubra doing to them?” she shouted above the din.

“What he had to.”

The abusive light died and the sound faded away. Dariat could see the pile of polyp now, eighty metres ahead. A crescent-shaped sliver of light straddled it, seeping in from the station beyond.

Their feet began to splash through rivulets of water flowing down the tunnel. Tatiana grimaced as they reached the foot of the blockage, and hitched her skirt up.

Bonney listened to the frantic shouting all around her, counting up the incidents, the number of casualties. They’d got off lightly. And she knew that was wrong.

“Quiet,” she bellowed. “How many stations attacked? Total?”

“Thirty-two,” one of the deputies said.

“And over fifty attacks altogether. But we’ve only lost about seventy to eighty people in the stations. Rubra’s just getting rid of the sentries we posted. If he wanted to seriously harm us he’d do it when the wrecking crews were down there.”

“A diversion? Dariat’s somewhere else?”

“No,” she said. “Not quite. We know he uses the tubes to get around. I’ll bet the little shit’s in one right now. He must be. Only we’ve already blocked him. Rubra is clearing the sentries out of the way so Dariat can sneak through. That’s why he spread the attacks around, so we’d think it was a blanket assault.” She whirled around to face a naked polyp pillar and grinned with malicious triumph. “That’s it, isn’t it, boyo? That’s what you’re doing. But which way is he going, huh? The starscrapers are dead centre.” She shook her head in annoyance. “All right you people, get sharp. I want someone down in each and every station Rubra attacked. And I want them down there now. Tell them to make sure they don’t step in the water, and be on the lookout for servitors. But get them down there.”