Tom Baker as The Doctor

Lalla Ward as Romana

David Brierly as K9 (voice)

Lewis Fiander as Tryst

David Daker as Rigg

Geoffrey Bateman as Dymond

Jennifer Lonsdale as Della

Stephen Jenn as Secker

Richard Barnes as Crewman

Barry Andrews as Stott

Geoffrey Hinsliff as Officer Fisk

Peter Craze as Officer Costa

Annet Peters as Passenger

Lionel Sansby as Passenger

Maggie Petersen as Passenger

Sebastian Stride as Crewman

Eden Phillips as Crewman