Set in the year 2089, huge machines known as Tripods have taken over earth with humanity existing in middle-age-type farming communities. Nobody rebels against this because humanity is mind-controlled via a cap which becomes compulsory from the age of 16. Will and his cousin Henry are not so keen on being capped and run away to the White Mountains to join the free people. On the way, they are joined by a French chap called Beanpole. The first series deals with the three friends making their way to the White Mountains to join the uncapped (and free) people.