A freak accident leaves two dangerously unstable spacecraft locked together, and a horde of monsters unleashed on their passengers.
Tom Baker
The Doctor
Lalla Ward
Romana
David Brierly
K9 (voice)
Lewis Fiander
Tryst
David Daker
Rigg
Geoffrey Bateman
Dymond
Jennifer Lonsdale
Della
Stephen Jenn
Secker
Richard Barnes
Crewman
Barry Andrews
Stott
Geoffrey Hinsliff
Officer Fisk
Peter Craze
Officer Costa
