Last updated 24 March 2024


Episode 4

Series Episode Number: 268

World Premiere: Sat 11 Apr 1970 - 5:44pm BST [BBC One] (United Kingdom)
First Broadcast: Thu 16 Oct 1975 - 6:30pm CDT [WTTW 11 Chicago]
Running Time: 24 minutes 37 seconds

9.30 Million (UK)

Appreciation Index: 58 (UK)

Chart Position: 46 () (UK)

Recorded on Fri 06 Mar 1970 in Television Centre 3
Archive State: PAL Restor



Liz has been captured by Reegan who is holding the three aliens captive. The Doctor suspects Quinlan's part in the conspiracy, but Quinlan is killed before he can reveal the truth.


Production Team hide uncredited
WriterDavid Whitaker (credit only)Info
WriterMalcolm Hulke (uncredited)Info
WriterTerrance Dicks (uncredited)Info
DirectorMichael Ferguson
ProducerBarry Letts
DesignerDavid Myerscough-Jones
Script EditorTerrance Dicks
Special SoundBrian Hodgson (uncredited)
and BBC Radiophonic Workshop (uncredited)
CostumesChristine Rawlins (uncredited)
Make-upMarion Richards (uncredited)
Action by HAVOC (uncredited)
Visual Effects DesignerPeter Day
Film CameramanA A Englander
Film CameramanTony Leggo
Film EditorDon Godden
Incidental MusicDudley Simpson
Title MusicRon Grainer
and BBC Radiophonic Workshop (uncredited)
Studio LightingRalph Walton (uncredited)
Studio SoundGordon Mackie (uncredited)
Technical ManagerBernard Fox (uncredited)
Vision MixerJohn Barclay (uncredited)
Grams OperatorAndy Stacey (uncredited)
Inlay OperatorAlan Gomery (uncredited)
Production AssistantNicholas John (uncredited)
Assistant Floor ManagerMargot Hayhoe (uncredited)
Floor AssistantJohn Turner (uncredited)
AssistantPauline Silcock (uncredited)
Location Make-UpTeresa Wright (uncredited)
Film SoundDoug Mawson (uncredited)
Assistant Sound RecordistMervin Broadway (uncredited)
Film Camera AssistantRoger Twyman (uncredited)
Film Camera AssistantNigel Walters (uncredited)
Videotape EditorJeff Higgs (uncredited)
Videotape EditorRon Bowman (uncredited)
Design AssistantDick Coles (uncredited)
Production SecretarySandra Brenholz (uncredited)
Director's AssistantKate Nemet (uncredited)
Artist BookingBarbara Buchanan (uncredited)
DresserArthur Funge (uncredited)
DresserJean Holder (uncredited)
Title Music ArrangerDelia Derbyshire (uncredited)
Title SequenceBernard Lodge (uncredited)