Last updated 24 March 2024


Episode 7

Series Episode Number: 278

World Premiere: Sat 20 Jun 1970 - 5:15pm BST [BBC One] (United Kingdom)
First Broadcast: Thu 6 Nov 1975 - 6:30pm CST [WTTW 11 Chicago]
Running Time: 24 minutes 33 seconds

5.50 Million (UK)

Appreciation Index: 60 (UK)

Chart Position: 79 () (UK)

Recorded on Fri 29 May 1970 in TC3 / TC6
Archive State: RSC conver



The Doctor has escaped the doomed, parallel Earth and has returned to his own world where he attempts to put a halt to the drilling project.


Production Team hide uncredited
WriterDon Houghton
DirectorBarry Letts (uncredited)
DirectorDouglas CamfieldInfo
ProducerBarry Letts (uncredited)
DesignerJeremy Davies
Script EditorTerrance Dicks
Special SoundBrian Hodgson
Special Sound BBC Radiophonic Workshop
Studio LightingJohn Green
Studio SoundJohn Staple
Film CameramanFred Hamilton
Film SoundGraham Hare
Film EditorMartyn Day
CostumesChristine Rawlins
Make-upMarion Richards
Visual Effects DesignerLen Hutton
Title MusicRon Grainer
and BBC Radiophonic Workshop
Technical ManagerLance Wood (uncredited)
Vision MixerJohn Gorman (uncredited)
Grams OperatorTony Philpott (uncredited)
Production AssistantChris D'Oyly-John (uncredited)
Assistant Floor ManagerSue Hedden (uncredited)
Floor AssistantFrank Mullan (uncredited)
Make-Up AssistantJudy Cain (uncredited)
Make-Up AssistantSue Duckworth (uncredited)
Make-Up AssistantIrene Walls (uncredited)
Scene CrewBrian Mitchell (uncredited)
Scene CrewBrian West (uncredited)
Costume AssistantTerry Styles (uncredited)
Costume AssistantPat Trigger (uncredited)
Film Camera AssistantHugh Miles (uncredited)
Film Sound AssistantJack Curtis (uncredited)
Director's AssistantSue Upton (uncredited)
Title Music ArrangerDelia Derbyshire (uncredited)
Title SequenceBernard Lodge (uncredited)