Last updated 24 March 2024


Part One

Series Episode Number: 398

World Premiere: Sat 19 Apr 1975 - 5:36pm BST [BBC One] (United Kingdom)
First Broadcast: Wed 19 Mar 1980 - 5:30pm CST [WTTW 11 Chicago]
Running Time: 24 minutes 19 seconds

9.50 Million (UK)

Appreciation Index: 57 (UK)

Chart Position: 24 () (UK)

Recorded on Tue 03 Dec 1974 in TC1



The Doctor, Sarah and Harry return to Nerva, but at an earlier point in time. The crew are dying and blame a space plague, but the Doctor suspects a survivor may be responsible.


Production Team hide uncredited
WriterGerry Davis
DirectorMichael E Briant
ProducerPhilip Hinchcliffe
DesignerRoger Murray-Leach
Script EditorRobert Holmes
Film CameramanElmer Cossey
Film SoundJohn Gatland
Film EditorSheila S Tomlinson
Studio LightingDerek Slee
Studio SoundNorman Bennett
Costume DesignerPrue Handley
Make-upCecile Hay-Arthur
Visual Effects DesignerJim Ward
Incidental MusicCarey Blyton
Special SoundDick Mills
Title MusicRon Grainer
and BBC Radiophonic Workshop
Title SequenceBernard Lodge
Production Unit ManagerGeorge Gallaccio
Production AssistantJohn Bradburn
Assistant Floor ManagerRosemary Hester (uncredited)
Assistant Floor ManagerRuss Karel (uncredited)
Title Music ArrangerDelia Derbyshire (uncredited)
Floor AssistantSteve Haggard (uncredited)
Vision MixerNick Lake (uncredited)
Technical ManagerJohn Farr (uncredited)
Senior CameramanPeter Granger (uncredited)
Grams OperatorPaul Graydon (uncredited)
Inlay OperatorDave Jervis (uncredited)
Assistant Film CameramanJohn Harper (uncredited)
Assistant Film Sound RecordistBruce Galloway (uncredited)
Film LightingSid Morris (uncredited)
Film OperativeStan Cresswell (uncredited)
Film OperativeDon Mattinson (uncredited)
Make-Up AssistantJane Boak (uncredited)
Make-Up AssistantMartha Fisher (uncredited)
Make-Up AssistantMartha Livesley (uncredited)
Director's AssistantSue Mansfield (uncredited)
Incidental MusicPeter Howell (uncredited)Info