Three years ago, Earth was invaded by a race of robots who quickly took over. The robots, led by a figure called the Mediator, claimed they meant no harm and only wanted to study humans. They implanted devices in every human to prevent them from leaving their homes. In England, a man defies the rules and is disintegrated by a drone, leaving his son, Connor, to be taken in by a neighbor, Kate, who cares for multiple orphaned children. The children discover a way to temporarily disable their implants and sneak out to learn more about their missing loved ones. They find out unpleasant truths about a collaborator named Smythe and uncover a machine that erases memories but leaves people in a catatonic state. As they attempt to rescue their captured friends, chaos ensues, but ultimately, the children manage to outsmart their captors and escape with their lives, thanks to Connor's quick thinking.