It did enable her to understand his absences, however. After all, he was steering, as he sometimes said, the narrative of the world.

At length Lobsang snapped back. He didn’t refer to whatever had distracted him, and Agnes did not enquire.

He stood up, stretching his back, wiping his hands. ‘Done – provisionally. You know, I could make this bike the safest in the world. Never skid, never put you in harm’s way . . . What do you say?’

Agnes thought that over before she answered. ‘I’m sure you could, Lobsang. And I’m very impressed, I really am. And touched. But, you see, a motorbike like my Harley doesn’t want to be completely safe. A machine like this develops what can only be called a soul, don’t you think? And you have to let that soul express itself, not hobble it. Let the metal be hot, the engine hungry . . .’

He stood, and shrugged. ‘Well, here’s your machine, complete with its hungry engine. Please drive safely – but that, Agnes, in your case, is a wish, not an expectation.’

So she carefully wheeled the Harley out of the little workshop, and guided the bike through the still-sparse rush-hour traffic of this stepwise world, until she reached open country where she could let the machine play. The wind was strong, but once you got away from the creeping industrialization of this young city – modern-day satanic mills, mostly covered by hoardings and advertisements – you were in a better world, the air cleaner, thoughts less melancholy. Over the roaring of the Harley she sang Joni Mitchell numbers, following roads like black stripes through the snow banks all the way around the frozen lakes of Madison West 5.

When she got back, Lobsang told her that Joshua Valienté had come home. ‘I need to see him,’ Lobsang said urgently.

Agnes sighed. ‘But, Lobsang, Joshua might not be so keen to see you . . .’

5

ON THE DAY OF the launch of the expedition of the Armstrong and Cernan, Capitol Square, Madison West 5, was like a movie set, thought Captain Maggie Kauffman, not without pride.

Here she was with her crew (make that crews) at her side, drawn up in parade order before the steps of the Capitol building, under a clear blue Low-Earth January sky. The air was cold but blessedly free of the Datum’s smog and volcano ash. A presidential podium had been set up before the building’s wooden façade, a very mid-twenty-first-century image with hovering cameras and a fluttering flag, the holographic Stars and Stripes of America and its stepwise Aegis.

On the stage a few guests waited for the President himself, as he made his latest public appearance at his new capital. There was Admiral Hiram Davidson, commander of USLONGCOM, the Long Earth military command, and Maggie’s own overall superior. Beside him was Douglas Black, short, gaunt, bald as a coot and in heavy sunglasses. Black was a ‘close friend’ of the President as well as a ‘trusted adviser’, the gossip sites said. Translation: moneybags. He always seemed to show up at events like this. But that was the way of the world, as it had been long before Yellowstone, or Step Day.

Up there too was Roberta Golding, the very young, very slim, evidently very smart and now pretty famous young woman who had rocketed from internship to a place in the President’s kitchen cabinet in the space of a few years. Golding, as it happened, had once gone out with the Chinese on their own far-East expedition, as a western student on some kind of scholarship programme. She’d been only fifteen at the time, a rung in the ladder for her spectacular subsequent career. In fact Golding had worked with Maggie’s XO, Nathan Boss, advising on the planning of the new expedition to be launched today. Maggie supposed Golding had earned her place on the platform.

Surrounding the party was the usual apparatus of presidential security, including drone aircraft buzzing overhead, and marines stationed around the podium, heavily armed, watchful, some of them sporadically stepping into neighbouring worlds to keep a check on any threat coming from that invisible direction. Further out, a perimeter of police, military and civilian security kept the crowds at a respectable distance from the action. But these crowds were nothing like the numbers you’d once have got in Datum Washington, DC, Maggie thought, on such a day. They were mostly dressed in clothes befitting a still-young colonial city, coveralls and practical overcoats rather than suits, home-made moccasins and boots rather than patent leather shoes. And there were many, many little kids in their number. Since Yellowstone, indeed long before that great dividing line in history, the populations of the stepwise Americas had been booming, and now Cowley’s own policies with handouts and tax breaks were encouraging bigger families yet.

And beyond that the scattered sprawl of this new Madison spread away. The wide avenues and open development allowed Maggie a view all the way to the lakes that defined the geography of Madison on all the stepwise worlds, calm, ice white rimmed by blue, glittering in the low January sun. Within the framework of the sparse, elegant, very modern city planning bequeathed by this stepwise community’s original founders, smart new establishments that catered for the recent influx of politicos and staffers sat side by side with more practical enterprises, such as stables for your horse, not a hundred yards from the Capitol itself. It was nothing like the clutter of the Datum original before the nuke. But it was a beguiling mix of American traditions old and new.

Nobody begrudged Brian Cowley a Constitution-bending FDR-style third term. The consensus seemed to be that whatever the murky processes that had first propelled Brian Cowley to office back in 2036 – at the head of his destructive, divisive, ‘Humanity First’ anti-stepper movement – he’d stepped up to the plate when the supervolcano had gone up during his innings. Continuity in what was still an ongoing crisis had to be a good strategy, there was no alternative candidate right now who would obviously do a better job – and everybody could see how much the burden was taking out of Cowley himself, who was ageing before everybody’s eyes, live on TV. In fact his unofficial election slogan had been ‘It’s hurting me more than it’s hurting you.’

But with his background as a bar-room barnstormer, he did like to put on a performance.

Joe Mackenzie grumbled to Maggie now, as they waited in the gathering crowd, ‘What’s the man going to do, wait until we all pass out?’

‘Don’t exaggerate, Mac. The whole thing is a show. This expedition of the Armstrong and the Cernan, I mean. And damned expensive. We’ve had to wait for years to do this, while we all worked on the Yellowstone recovery. You can’t blame Cowley for milking the moment, that’s the whole point of it for him.’

‘Hmm,’ Mac grunted sceptically. He glanced around at the crews of the two craft in Maggie’s small squadron, his expression sour. ‘Some expedition.’

Maggie saw her people through his eyes: the Navy crew, the squads of marines adding some muscle. In there was Captain Ed Cutler, whom every man and woman in Maggie’s old command had once seen run nutso in Valhalla. There was the small Chinese contingent in their oddly ill-fitting uniforms, a non-negotiable offering of friendship, cooperation and so forth that had been part of the deal that had delivered the advanced Chinese stepper technologies for the US Navy’s newest ships.

And there were the trolls, three of them, a small family, wearing the armband stripes that designated them as co-opted members of Maggie’s crew. They were visibly unhappy to be stuck in a Low Earth, a world crowded with humanity’s stink and suffused with the peculiar mental pressure that generally kept trolls away from dense human populations – yet here they were, and Maggie allowed herself to be pleased by their loyalty.