A group of London teens find themselves in the middle of an alien invasion and fight to defend their tower block from some evil extraterrestrials in this stylish sci-fi romp from the producers of Shaun of the Dead and Scott Pilgrim vs. the World. Beset by a gang of young thugs as she passes through a South London housing estate, Sam (Jodie Whittaker) is in the midst of being robbed when a ball of light falls out of the sky, and destroys a nearby car. Frightened, she flees from the scene just before an unearthly beast emerges from the wreckage and attacks Moses (John Boyega), the leader of the youthful gang. In retaliation, Moses and his crew slay the creature, and take it to a local drug den owned by ruthless gangster Hi-Hatz (Jumayn Hunter) for safe keeping. Later, as the police assist Sam in pursuing her assailants, strange lights start to rain down on the streets, heralding the arrival of a second, more ferocious, wave of creatures. With the city under siege, there's no place left to run. Quickly realizing she's going to have to fight if she wants to survive, Sam once again crosses paths with the street-tough teens, but instead of running away vows to battle alongside them to the bitter end. Meanwhile, Moses becomes the primary target of the aliens, and the group arms themselves with everything from baseball bats to high-powered fireworks in the fight to save the human race.