Three years ago, Earth was conquered by a force of robots from a distant world. They have one rule: Stay in Your Homes. Step outside and you get one warning before you're vaporised by a massive robot Sentry, or a crawling Sniper, or a flying Drone. That's if the vast Cube doesn't incinerate you first. But Sean Flynn is convinced that his father--an RAF pilot who fought in the war--is still alive. And when he and his gang figure out a way to break the robots' curfew, they begin an adventure that will pit them against the might of the Robot Overlords.