If you're a discerning reader of fiction, two things – maybe three if you're particularly fussy – might put you off this book. The first is the blurb: "On board the moletrain Medes, Sham Yes ap Soorap watches in awe as he witnesses his first moldywarpe hunt". The second is the description of this novel as "for all ages". The third, well, perhaps you're the sort of reader who won't entertain anything that is science fiction or fantasy.
Don't let the first two derail you from trying out this wonderful, wonderful novel, and as for the third ... get a grip. Some of the finest writing, thinking and sheer joy is coming out of the SF/fantasy genre at the moment, especially in Britain, and Railsea is a very fine example indeed.
Railsea does indeed involve giant moles called moldywarpes, among other burrowing, mutated beasts that make the bulk of the land surrounding huddled human island communities into strictly no-go areas. The island communities are not oceanic, but rather waystations amid a vast, seemingly never-ending landscape of jumbled, interconnected train-tracks – the railsea of the title, which is plied by trains such as the Medes, on which young Sham works as an apprentice doctor.
The all-ages tag presumably derives from the fact that there's no sex and little bad language in Railsea. There is nothing juvenile or simplistic about China Miéville's far-future adventure, in which all traces of life today are reduced to mysterious salvage collected by the scattered remnants of humanity.
Railsea initially comes over as a cross between the 1990 movie Tremors and the most famous book by Miéville's near-namesake Herman Melville – Moby Dick. Sham rides the Medes as it hunts gigantic moles and other grotesques for food, dreaming of his true calling digging for salvage from the time long gone, while the captain of his train, Abacat Naphi, pursues her "philosophy": any railsea train captain worth her salt has lost a limb to a monster, which comes to represent an abstract concept, and devotes her life, Ahab-like, to hunting it down.
Sham's journey offers him hints as to the true nature of the railsea, and suggestions that there is indeed something beyond the evocative image of the world-spanning spaghetti of tracks and ties. Through his young protagonist's eyes, Miéville presents a future world that is wondrous and believable in equal measures, while never easing the pace of a runaway train ride of a novel.