The Doctor (Patrick Troughton), Jamie and Zoe land on the planet of the Gonds, the brightest of whom are periodically selected to serve the unseen Krotons, and never seen again. When Zoe and the Doctor are selected too, the battle is on to destroy the crystalline aliens.
Note: This is an imported product that has been officially rated by the Film and Video Labelling Body of New Zealand. As this is sourced from overseas, the discs may not play on standard DVD players.