15 years after a global apocalypse, mankind is on the verge of extinction. Civilisation no longer exists, food is scarce and most eke out a living by stealing and killing. One boy clings onto life in the desolate British countryside, where staying away from others has been key to his survival. But this self-imposed isolation comes to an abrupt end when he crosses paths with another group of survivors and faces an enemy far more savage than any of them could imagine.

Bethany has been kidnapped by Avondale's popular kids for a surprise birthday party to celebrate her sweet 16. They don't realize that Bethany is the target of the monstrous 'Thorn', and nothing will stand in his way.