The Doctor, fresh from averting disaster for his home world, finds himself in the TARDIS on a planet he recognizes. His arrival couldn’t be more opportune, as Leela (played by Louise Jameson) faces exile from her people. They join forces, and it soon becomes apparent to the forgetful Doctor (Tom Baker) that the warring Sevateem tribe is after him. The reason for this hostility unfolds gradually: two tribes exist on t…