The planet Mere's inhabatants have all disappeared except for one survivor left behind. Meanwhile, The Doctor and Martha arrive on New Savanah just as an explosion rocks the office of the Vedele Defense Systems Headquarters at the moment the board hands over control of the planet to the Earth Empire. Rushing to the scene to help, Martha is arrested as the Doctor comes to the rescue and finds out that the lead investigator is in on the plot. The Doctor discovers the defenses surrounding the main city have been deactivated as the wild population that had rejected the presence of the Earth Empire and their customs rush back into the city. In the chaos and confusion, the Doctor comes face-to-face with a "God" who is behind things, Bubastion.