“Last stop before Fairbanks. Time to stretch your legs, Newcomen.”

“I can stay here. I’ll just get in the way otherwise.”

Petrovitch pursed his lips. “You can mope all you like. But you’re not doing it on my time. Now, out of your seat, and come with me.”

“And how cold is it outside?”

“Why don’t you talk to your link and find out? It’s there: use it.”

When Newcomen discovered it was minus thirty-five, he rebelled. “No way.”

Petrovitch pointed through the windscreen at the next plane. A slit of orange light showed its cargo bay door was ajar. “We’re going as far as there, that’s all.”

“So whose plane is that?”

“This is the way it works: Freezone people don’t ask stupid questions because they’re not lazy and they can find out the answers for themselves. It means that conversations can be direct, to the point, and mercifully short.” He left it there, and made his way to the cabin door.

The ladder dropped its feet into the snow. Petrovitch trotted down and headed straight for the sliver of light. Minus thirtyfive was genuinely awful without the proper gear, enough to turn his skin waxy and freeze the liquid lubricating his eyes. As he approached the other plane, the door opened wider, and more light spilled out. A preternaturally tall figure stood inside, waiting.

Petrovitch turned sideways through the gap, making sure he didn’t touch any of the metal, and found himself enveloped in strong arms and a warm coat.

“Hey,” he said.

“Hey yourself,” she replied. “You made good time.”

“It’s fast, even if it does look like it’ll break if you drop it.”

Madeleine squinted through the door. “It will break if you drop it. You haven’t dropped it, have you?”

“Not a scratch on it. We might even be able to return it in one piece.”

“Something tells me that’s not going to happen.” She looked over his head. “Newcomen.”

“Mrs Petrovitch.” He stood in the doorway, looking uncertain.

“If you come in, I can close the door.” She let go of Petrovitch and thumbed the mechanism. The door cranked shut with a bang, and Newcomen shivered.

Madeleine threw another coat at him, and he caught it and put it on quickly. He noticed that beneath her own coat, she had an armoury hanging from her wide belt.

“Those don’t look like they’re for bears.”

“Is that what he told you?” She snorted. “And you believed him?”

Newcomen looked across at Petrovitch, who was sealing his coat at the front and lifting the fur-lined hood over his head.

“Doesn’t mean there aren’t bears, all the same.”

“Of course, if we’d done this my way…”

“And you were voted down.” Petrovitch’s face was framed by the hood. “There’s still plenty of time for this to turn into a hot war.”

It was then that Newcomen realised just what was in the cargo hold with him. Long metal crates, with serial numbers and scripts in different languages. “These boxes. You can’t be serious.”

Petrovitch looked around him. He knew what was inside each one, and it still surprised him. “Maddy figures that turning up to a fight with nothing more than good intentions is a quick way to get yourself killed. But we’re not looking to start the fight.”

“They are,” said Madeleine. “They’ve been moving assets north for the past week.”

“Assets?” asked Newcomen. “What sort of assets?”

“We can’t see through the tops of the trucks hauling north on the Dalton Highway, but we’ve a pretty good idea of what they’re carrying. We thought we might need something to level the odds.” She rested a foot on top of a steel case that looked like it might contain a surface-to-air missile launcher.

“You can’t start a war. Up here. That’s… ridiculous. There’s two of you.” Newcomen saw that both Petrovitchs wore identical expressions. “All these planes are yours, aren’t they?”

“They might be.” Madeleine jerked her head at her husband. “And he’s never needed any help starting a war. The rest of us are only here to make sure it’s done right.”

“You’re all insane.”

“You think so?” Petrovitch tapped Newcomen’s top pocket. “Get your reader out. Michael has something to show us.”

Newcomen fumbled with his cold fingers for the plastic rectangle. Petrovitch didn’t need one, hadn’t needed one for a decade. He called up his sandbox and sat down beside it with Michael.

“Hey. What’s the news?”

[We believe SkyShield targeted a satellite of currently unknown origin. If our theory, which currently enjoys some seventy per cent confidence, is correct, it has serious implications for global communications in general, and the integrity of the Freezone in particular.]

Ten years on from the lanky Japanese kid who’d guided him though the Outie war, Michael’s preferred form was disturbingly like a young Hamano Oshicora. He could be literally anything he wanted, but this was his settled identity. It did no harm, and Petrovitch wondered if the AI had done this consciously: he never asked, and Michael never offered an answer of his own.

“No one’s complained about any missing hardware.”

[Which indicates that there are two secrets here: firstly, why the satellite’s owners wish to remain anonymous, and secondly, what reason the Americans had for shooting it down,] said Michael.

“Unless the Yanks are testing out a new anti-satellite system on a bird they’ve put up themselves, in preparation for blanking out the sky for the rest of us.”

[This is a possibility that falls within the thirty per cent uncertainty. Other options include a malfunction of SkyShield, the accidental targeting of a bolide, or indeed the deliberate targeting of a piece of debris that might have posed a threat to people on the ground.]

“But most of the analysts don’t buy any of that.” Petrovitch leaned over his sandbox, which transformed itself into a map of the northern hemisphere, pole uppermost. “Show me.”

Michael started to draw his explanation. Red lines representing the orbits of objects in space, blue to mean the objects themselves.

[The raw data has been extrapolated to a best-fit scenario, but some things we can be certain of: a SkyShield interceptor in Low Earth Orbit fires a kinetic energy weapon at zero nine thirteen, Universal Time. Eight seconds later, a flash is observed one hundred and twenty kilometres away from the interceptor by a Freezone micro-satellite. The images captured are compromised by the low angle at which they were acquired, taken through the outer reaches of the atmosphere.]

“The originals look like govno, right?”

[A considerable amount of processing was required to extract useable data, yes. The object re-entered the Earth’s atmosphere and, at zero nine twenty-three Universal Time, caused a seismic event measuring three point seven Richter. This equates to a yield of approximately one half to one third of a megatonne ten kilometres above the epicentre, south of Prudhoe Bay, Alaska.]

“That’s way too much for a satellite.” Petrovitch frowned and looked at the blue line described in the air in front of him, which arced down from space and terminated above the North Slope. “Or way too much for a regular satellite. What the hell did they have in there?”

[Barring a matter – antimatter collision, the conclusion is that only a nuclear explosion could provide such prompt energy.]

“A nuclear power plant won’t blow up just because you hit it.”

[Again, it is more likely that the explosion was a deliberate fail-safe against the re-entry and recovery of identifiable debris.]

“So, to summarise: someone put a satellite into orbit, carrying something so secret that they put a nuclear bomb on board too. The Americans got wind of it and took it out. The satellite starts to drop from the sky, and the bomb goes off before it hits the ground. Is that about right?”

[With the usual caveats, yes.]

“Then why the huy haven’t we heard anything about this before now? We’re supposed to be the planet’s most sophisticated information-gathering system, working every minute of every day, yet we miss something like this? Yobany stos, this is not just pizdets, this is a whole new category of pizdets.”