The Doctor meets Leela and the primitive Sevateem Tribe, and finds himself hailed as 'The Evil One'. Leela shows him a huge carving of his face in a cliff...The Tribe is actually descended from a stranded survey team , While the descendents of the ship's Technicians - The Tesh - still tend the ship's equipment. Both tribes are 'Governed by the computer Xoanon, which has a split personality - Some of it The Doctors...