Last updated 09 January 2020


Part One

Series Episode Number: 480

World Premiere: Sat 2 Sep 1978 - 5:44pm BST [BBC One] (United Kingdom)
First Broadcast: Sun 23 Aug 1981 - 11:00pm CDT [WTTW 11 Chicago]
Running Time: 25 minutes 2 seconds

8.30 Million (UK)

Appreciation Index: 59 (UK)

Chart Position: 42 () (UK)

Recorded on Sun 09 Apr 1978 in TC4



The Guardian of Time gives the Doctor a difficult task, and a new assistant. Together they must search for the six segments of the Key to Time, to prevent the Universe from being plunged into eternal chaos.

On their mission, the Doctor and Romana travel to the planet Ribos where the first segment of the key is protected by the monstrous Shrivenzale.


Production Team hide uncredited
WriterRobert Holmes
DirectorGeorge Spenton-Foster
ProducerGraham Williams
DesignerKen Ledsham
Script EditorAnthony Read
Costume DesignerJune Hudson
Make-up ArtistChristine Walmesley-Cotham
Visual Effects DesignerDave Havard
Electronic Effects OperatorDave Chapman
Videotape EditorJohn Turner
Studio LightingJim Purdie
Studio SoundRichard Chubb
Production AssistantJane Shirley
Production Unit ManagerJohn Nathan-Turner
Incidental MusicDudley Simpson
Special SoundDick Mills
Assistant Floor ManagerRichard Cox (uncredited)
Make-Up AssistantDenise Baron (uncredited)
Make-Up AssistantJuliette Mayer (uncredited)
Make-Up AssistantSuzanne Jansen (uncredited)
Visual Effects AssistantRoger Turner (uncredited)
Visual Effects AssistantNigel Brackley (uncredited)
Technical ManagerPeter Grainger (uncredited)
Vision MixerSue Thorne (uncredited)
Grams OperatorMartin Ridout (uncredited)
Floor AssistantPeter Leslie (uncredited)
Director's AssistantWendy Plowright (uncredited)
Title MusicRon Grainer (uncredited)
Title Music BBC Radiophonic Workshop (uncredited)
Title Music ArrangerDelia Derbyshire (uncredited)
Title SequenceBernard Lodge (uncredited)