The more Tom learns about the world London travels over, the more he begins to realize that someone needs to take action before history repeats itself. The adventures which await our young hero star a cast of unforgettable characters including a deformed girl with a painful past, some museum curators with more gumption than meets the eye, a charming but mysterious rebel pilot, treacherous villains with impeccable manners, and a roving town operated by greedy pirates.

When he rescues his hero from a revenge-bent young assassin girl, though, Tom finds himself stranded on solid ground while London thunders on in search of better hunting grounds, and he must come to terms with the numerous secrets which suggest that London is not as ideal as its townsfolk (and passengers) assume.

After all, his hero Thaddeus Valentine – the dashing airship explorer and collector of Old-Tech like mysterious compact discs and other artifacts from before the Sixty Minute war – is a Londoner, and Tom wants to be just like Valentine someday, despite his own lowly status as an orphan apprentice at the museum. London, his beloved city, is on the move and he’s sure it’s the best city-on-wheels in the whole world. In all his years as an apprentice historian, Tom Natsworthy has never doubted the moral supremacy of Municipal Darwinism that is, mobilized cities and towns hunting each other down and consuming weaker suburbs for resources all over the ravaged carcass of Earth.

Mortal Engines by Philip Reeve