Imagine a future in which the city of London has been rebuilt atop enormous caterpillar treads, “a moving mountain of metal that rose in seven tiers like the layers of a wedding cake, the lower levels wreathed in engine smoke, the villas of the rich gleaming white on the higher decks, and above it all the cross on top of St. Paul’s Cathedral glinting gold, two thousand feet above the ruined earth.” Following the enormously destructive Sixty Minute War, scarce resources have forced cities and towns in Europe to go mobile, ranging the land in search of smaller, weaker communities to prey upon in a practice known as Municipal Darwinism. A lowly third-class apprentice aboard London, Tom plunges—literally—into a tangle of conspiracy, murder, and greed when he falls straight through a waste chute in pursuit of a would-be assassin, Hester. Dumped like trash onto the wasted earth, Tom and Hester watch London trundle off into the distance before launching into a whirlwind adventure. Traveling on foot, by airship and aboard a pirate suburb, always one step ahead of a relentless cyborg killer (shades of a Schwarzenegger-like Terminator), the two struggle to return to London. Always exciting and frequently grisly (almost all the main characters exit in violent death), Mortal Engines is undeniably distinctive and imaginative. Science fiction and fantasy readers will be happily absorbed into this Dickensian future, and pleased that the series title, “The Hungry City Chronicles,” promises more of Reeve’s roving cities on the horizon. (Ages 10–14)