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.
Tom Baker
The Doctor
Mary Tamm
Romana
John Leeson
K-9 (voice)
Bruce Purchase
The Pirate Captain
Andrew Robertson
Mr. Fibuli
Rosalind Lloyd
Nurse
David Warwick
Kimus
David Sibley
Pralix
