The Doctor and Romana learn the second segment of the Key to Time is on the planet Calufrax. Yet they arrive on a planet called Zanak, which has been hollowed out and fitted with hyperspace engines, allowing its insane, half-robot Captain to materialise it around smaller planets and plunder their resources.

Cast:Tom Baker, Mary Tamm, John Leeson, Bruce Purchase, Andrew Robertson, Rosalind Lloyd,

Genre:Action, Adventure, Drama, Science Fiction, TV Movie,

country:United Kingdom,

Production:BBC,