In this serial, the new Doctor (Troughton) and his travelling companions Polly (Anneke Wills) and Ben (Michael Craze) land on the planet Vulcan in the year 2020. There they find an Earth colony, where the lead scientist Lesterson (Robert James) discovers a 200-year-old alien capsule containing three inactive Daleks. Once brought back to life, the Daleks act as the colony's servants, but all they really want is power. Although audio recordings, still photographs, and clips of the story exist, no episodes of this serial are known to have survived.