Mortal Engines is based on the award-winning novel, with the same name, by British author Philip Reeve. The action takes place in a post-apocalyptic future, where the cities got wheels and turned into virtually huge vehicles. There is, however, a struggle for the resources needed to maintain such a city (through organized attacks against smaller and more vulnerable settlements). But activists also appear to be using less resource-friendly resources, and when, in London, Tom Natsworthy opposes an attack on another city, he is banished, along with another wicked one. The two of them will have to struggle hard through the ruins of the planet to defeat a plan that puts Terra in danger.