Journalist Sarah Jane Smith is impersonating her aunt, virologist Lavinia Smith, in order to gain access to a research centre where top scientists are being held in protective custody while UNIT investigates the disappearance of a number of their colleagues. The missing scientists have been kidnapped by a Sontaran, Linx, and taken back to medieval England, where they are working under hypnosis to repair his crashed spaceship.

Starring Jon Pertwee as the Third Doctor

dr who, Jon Pertwee, john pertwee, third doctor, Sarah Jane