Like a lot of great SF, this starts with just one single premise. What if we suddenly discovered an unlimited number of pristine Earths, and we could all travel between them at the flick of a switch?
One day, a blueprint for a very simple electrical device appears on the Internet. Thousands of people build one of these little boxes, flick the switch — and disappear. They’ve “stepped” to an alternative Earth, untouched by humans. From there they can go back or continue on to a multitude of more-or-less parallel Earths. The story follows a number of characters through the massive social changes that follow on from this: suddenly there are endless frontiers, on pristine worlds where environmental degradation and climate change are irrelevant. There is also a lot of sci-fi adventure as people explore millions of the alternative Earths, some of which are very different — essentially alien worlds. And they don’t just stop there — the third book in the series is called The Long Mars.
The characters are interesting and fun to read about. There’s the normal guy with super(-stepping) powers; the cantankerous and brilliant inventor; the tough frontierswoman; and of course the Tibetan auto mechanic reincarnated as an omnipotent distributed AI system.
After the initial splash of brilliance, I thought the first book got a little bit slow towards the end. The second and third both picked up the pace with more fun ideas — I read them on the trot. There’s a lot of exposition, unavoidable in SF as all the new concepts have to be introduced and explained. But the writing is mostly pretty snappy and there are touches of Pratchett humour gently sprinkled throughout.
I haven’t read the final two books in the series yet — I’m taking a little break. But I will read The Long Utopia soon, and if it’s as good as the others then I will pick up The Long Cosmos straight after that.