“The AT Squad teams will be over the bus in ninety seconds,” Bernard Gibson said. “We’ll see exactly what’s going on then.”

Ralph datavised a tactical situation request into the hub’s processor array. His neural nanonics visualized a map of Xingu, a rough diamond with a downward curling cat’s tail. Forty-one of Moyce’s delivery lorries had been located and annihilated now, green and purple symbols displaying their movements, the locations when they were targeted. The bus was a virulent amber, proceeding down the M6 motorway which ran the length of Mortonridge, the long spit of mountainous land which poked southwards across the equator.

He switched to accessing the sensor suite on the lead hypersonic. The plane was just decelerating into subsonic flight. There was nothing any discrimination filter program could do about the vibration as it aerobraked. Ralph had to wait it out, impatience heating his blood feverishly. If Angeline Gallagher wasn’t on the bus, then they’d probably lost the continent.

The M6 was laid out below him in the clear tropical air. The hypersonic’s shaking damped out, and he could see hundreds of stationary cars, vans, buses, and lorries parked on the motorway’s service lanes. Headlights illuminated the lush verges, hundreds of people were milling around, some even settling down for midnight picnics by their vehicles.

The static pageant made the bus easy to spot, the one moving light source on the motorway, heading south at about two hundred kilometres an hour. It roared on past the riveted spectators lining the lane barrier, immune to the priority codes being fired into its circuitry from the motorway’s route and flow processors.

“What the hell is that thing?” Vicky Keogh voiced the unspoken question of everyone accessing the hypersonic’s sensor suite.

The Longhound Bus Company had a standardized fleet of sixty-seaters made on the Esparta continent, with a distinct green and purple livery. They were used all over Ombey, stitching together every continent’s cities and towns with an extensive, fast, and frequent service. The principality didn’t yet have the economy or population to justify vac train tubes linking its urban areas like Earth and Kulu. So the Longhound buses were a familiar sight on the motorways; more or less everyone on the planet had ridden on one at some time in their lives.

But the runaway vehicle speeding down the M6 looked nothing like a normal Longhound. Where the Longhound’s body was reasonably smooth and trim, this had the kind of sleek profile associated with the aerospace industry. A curved, wedge-shaped nose blending back into an oval cross-section body, with sharp triangular fin spoilers sprouting out of the rear quarter. It had a dull silver finish, with gloss-black windows. Greasy grey smoke belched out of a circular vent just behind the rear wheel set.

“Is it on fire?” a disconcerted Warren Aspinal asked.

“No, sir.” Diana sounded ridiculously happy. “What you’re seeing there is its diesel exhaust.”

“A what exhaust?”

“Diesel. This is a Ford Nissan omnirover; it burns diesel in a combustion engine.”

The Prime Minister had been running his own neural nanonics encyclopedia search. “An engine which burns hydrocarbon fuel?”

“Yes, sir.”

“That’s ridiculous, not to mention illegal.”

“Not when this was built, sir. According to my files, the last one rolled off the Turin production line in 2043 AD. That’s the city of Turin on Earth.”

“Have you a record of any being imported by a museum or a private vehicle collector?” Landon McCullock asked patiently.

“The AIs can’t find one.”

“Jenny Harris reported a phenomenon similar to this back on Lalonde,” Ralph said. “She saw a fanciful riverboat when I sent her on that last mission. They’d altered its appearance so it seemed old-fashioned, something from Earth’s pre-technology times.”

“Christ,” Landon McCullock muttered.

“Makes sense,” Diana said. “We’re still getting a correct identification code from its processors. They must have thrown this illusion around the Longhound.”

The hypersonic closed on the bus, sliding in over the motorway, barely a hundred metres up. Below it, the omnirover was weaving from side to side with complete disregard for the lane markings. The ceaseless and random movement made it difficult for the pilot to stay matched directly overhead.

Ralph realized what had been bothering his subconscious, and requested a visual sensor to zoom in. “That’s more than just a holographic illusion,” he said after studying the image. “Look at the bus’s shadow under those lights, it matches the outline.”

“How do they do that?” Diana asked. Her voice was full of curiosity, with a hint of excitement bleeding in.

“Try asking Santiago Vargas,” Vicky Keogh told her sharply.

“I can’t even think of a theory that would allow us to manipulate solid surfaces like that,” Diana said defensively.

Ralph grunted churlishly. He’d had a similar conversation back on Lalonde when they were trying to figure out how the LDC’s observation satellite was being jammed. No known principle. The whole concept of an energy virus was a radical one.

“Possession,” Santiago Vargas called it.

Ralph shivered. His Christian belief had never been that strongly rooted, but like a good Kingdom subject, it was always there. “Our immediate concern is what do we do about the bus. You might manage to land AT Squad teams on the thing if they were equipped with airpack flight suits, but they can hardly jump down from the hypersonic.”

“Use the SD platforms to chop up the motorway ahead of it,” Admiral Farquar suggested. “Force it to stop that way.”

“Do we know how many people were on board?” Landon McCullock asked.

“Full complement when it left Pasto spaceport, I’m afraid,” Diana reported.

“Damn. Sixty people. We have to make at least an effort to halt it.”

“We’d have to reinforce the AT Squads first,” Ralph said. “Three hypersonics isn’t enough. And you’d have to stop the bus precisely in the centre of a cordon. With sixty possible hostiles riding on it, we’d have to be very certain no one broke through. That’s wild-looking countryside out there.”

“We can have reinforcements there in another seven minutes,” Bernard Gibson said.

“Shit—” It was a datavise from the pilot. A big javelin of white fire streaked up from the bus, punching the hypersonic’s belly. The plane quaked, then peeled away rapidly, almost rolling through ninety degrees. Bright sparkling droplets of molten ceramic sprayed out from the gaping hole in its fuselage to splash and burn on the motorway’s surface. Its aerodynamics wounded, it started juddering continuously, losing height. The pilot tried desperately to right it, but he was already too low. He came to the same conclusion as the flight computer and activated the crash protection system.

Foam under enormous pressure fired into the cabin, swamping the AT Squad members. Valency generators turned it solid within a second.

The plane hit the ground, ploughing a huge gash through the vegetation and soft black loam. Nose, wings, and tailplane crumpled and tore, barbed fragments spinning off into the night. The bulky cylinder which was the cabin carried on for another seventy metres, flinging off structural spars and smashed ancillary modules. It came to a jarring halt, thudding into a steep earthen bluff.

The valency generators cut off, and foam sluiced out of the wreckage, mingling with the mud. Figures stirred weakly inside.

Bernard Gibson let out a painful breath. “I think they’re all okay.”

One of the other two hypersonics was circling back towards the crash. The second took up position a respectful kilometre behind the bus.

“Oh, Christ,” Vicky Keogh groaned. “The bus is slowing. They’re going to get off.”

“Now what?” the Prime Minister demanded. He sounded frightened and angry.