William Calder didn’t think much of it. Aged twenty-seven, with a wife, Jenny, and two kiddies in a tenement block in the Gorbals back in Glasgow, he’d always known the work on this exploratory oil rig was going to be hard and dirty and dangerous, even before Scotland started bloody blowing up. Twelve hours on, twelve hours off, weeks or months away from home; William just kept himself to himself and got through his work, like serving a sentence, which, if truth be known, William had done once or twice in his younger days.

But now it was nearly the end of his tour of duty — nearly the end for everybody, as the rig was going to be evacuated in a few days because of the volcano stuff — and William would be going home with his bank account stuffed with money, more than enough to get his young family out of Glasgow for good, and into some safe bolt hole in England, as far south as they could bloody go without falling into the English Channel.

So he was sitting with a six-pack in the cinema, watching Independence Day for the fourth time, when the first explosion came.

The rig shuddered, and there was a wail like a scream.

“Jesus Christ, that’s a gas leak,” said Jackie Brown, one of the blasting foremen.

Everybody stood up.

The film jammed, and burned through with shocking suddenness, a black circle just gushing outwards across the screen.

Then the plastic walls of the room started to melt, and the workers, men and women alike, started to run.

In the corridor outside, William saw people grabbing at metal railings. There was a sound of sizzling, like bacon, and people screamed. The railings were too hot to touch.

William tried to get to the heli-deck, but that was a waste of time. The stairwells were jammed with people, and the heat was already intense. So Jackie Brown turned and said, “Come on, boys,” and he started to push his way deeper into the rig.

Eventually they got out through the drill deck, to a lower level which took them out to the foghorn platform. William blinked in the sudden light, breathed in fresh air. The sea was calm, the day bright. People were running everywhere.

There was no sign of rescue, no choppers. There was a gigantic pall of black smoke, though, hanging over the eastern horizon.

“Shite,” somebody said. “They must have nuked Glasgow.”

William could see the gas flare, the system that burned off the inflammable gases produced by the thimblefuls of crude oil that was all they had managed to dredge up, here in the Channel between Britain and Ireland. The flare was burning furiously, much more intensely than usual.

And then, as William watched, the flare exploded. The light was dazzling, brighter than the sun, and you could feel the energy pouring out of it.

The bang was followed quickly by heavy, mortar-like crumps coming from the heart of the rig.

Jackie Brown was standing beside him. “That’s the bloody diesel tanks,” Jackie hissed. He was nursing burned hands.

…And now a fireball rose with a kind of majesty through the heart of the rig. It was the central gas jet. William could hear the tearing of metal, the cracking roar of explosion after explosion, as the rig tore itself to pieces.

The deck beneath him tipped — the whole rig was coming apart — and now, oh God, some of the deck plates were buckling.

The flames were towering over his head.

Jackie Brown clapped William’s shoulder. Jackie, in his fifties, had seen it all before. “Fry and die, or jump and try,” he shouted, and he jumped without hesitation off the tipping side.

There was oil burning on the surface of the water, which was all of a hundred feet below. The heat was already unbearable — William thought of Jenny, and wondered where she was now. He wondered if he should take off his boots first. He jumped.

Henry was pressed back into his couch.

The ignition was a sharp rattle, the engine noise a dull roar, transmitted through the fabric of the Soyuz. Suddenly Arkady’s knee, pressing against his, felt heavy, unbearably bony.

He heard a clattering noise from above as some loose piece of gear fell through the orbital module. The pressure was heavy; he knew it was only a fraction of Earth-normal gravity, but, after three days of weightlessness, it felt like five G.

Arkady and Geena scanned their controls. “Pressures coming up nicely,” said Geena.

Time seemed to stretch, flowing like mercury. Henry knew that if the burn was too short, they would finish up on some weird, perhaps unrecoverable orbit. But if the burn was even a few seconds too long then instead of missing the Moon by that crucial sixty-nine miles or so, they would drive into its eternal surface, creating one more crater among billions.

It was the longest four minutes of his life.

“Burnout coming up,” Geena said. “Chamber pressures dropping to fifty psi… three, two, one.”

The engine thrust died in a snap; the vibration and noise disappeared, and Henry was thrown forward against his straps.

The fires around George Square seemed to be growing, not diminishing, and still the jolts and aftershocks came. Jenny sat squat on the ground, her hands spread out, not daring even to stand.

In one place, in the west of the city, there was a kind of fountain, of steam and fire, that reached hundreds of feet into the air. Great glowing rocks shot out of it, and where they landed, like bombs, new fires started. A volcano, she guessed, right here in the middle of Glasgow.

People were gathering in the Square, in ones and twos or small groups. Some were burned, or were nursing damaged limbs or heads, crudely bandaged, or were carrying other injured.

Some of them had stories, and Jenny listened in horror.

There was the woman who had come across the Glasgow Bridge, to flee the fires on the south bank. The bridge had collapsed, and the woman, with dozens of others, had ended up creeping across a single iron beam. But there had been a panic, a rush, crushing and suffocating, and fifty or sixty had been sent headlong into the waters of the Clyde. When she looked down, the woman saw maybe a hundred people in the water, some swimming or clinging to flotsam, some already dead. There were small boats trying to pick up survivors, but their task seemed hopeless.

Here was a man who had seen Argyle Street crack right open, and fill up with a bizarre mix of rushing water and a wall of fire, from burst mains; the crowds had fled through streets that, even where intact, were jungles of downed power lines, bricks, rubble, shattered glass and felled lampposts and burning cars.

Another woman barely escaped when the motorway bridge collapsed, steel reinforced concrete twisting like plasticine.

An elderly woman had been asleep in her bed, when her high-rise block collapsed. Her first floor flat had become the ground floor; the lower level had telescoped down to eighteen inches. When she clambered out, dazed, she found people trying to mount a rescue operation, shimmying down fire hoses, people screaming and crawling over each other.

There was the tale of a man who was buried up to his neck in the ruins of the City Chambers. When they dug him out, the whole of his lower body was crushed flat, like a tiger rug, and he had time to see it that way, before he died.

Another woman had been trapped by her legs under a beam. Her son had tried to free her by, good God, amputating her legs. But he could only remove one before the flames beat him back.

…And so on; everybody had a story to tell, it seemed.

More and more people crushed into the Square. The fires were still growing, all around the skyline. New arrivals said the big fires on the south bank had leapt the Clyde. That big explosion was the fuel depot at the Central Station going up.

And while all that marched up from the south, another great blaze was licking its way down from the wreckage of the Buchanan Centre to the north.