Last updated 09 January 2020


Part One

Series Episode Number: 402

World Premiere: Sat 30 Aug 1975 - 5:46pm BST [BBC One] (United Kingdom)
First Broadcast: Tue 25 Mar 1980 - 5:30pm CST [WTTW 11 Chicago]
Running Time: 21 minutes 41 seconds

8.40 Million (UK)

Appreciation Index: 59 (UK)

Chart Position: 29 () (UK)

Recorded on Mon 07 Apr 1975 in TC3 at these locations
BBC Genome Project: see entry

BBC Programme Page
IMDb


The Doctor, Sarah and Harry return to Earth to help the Brigadier discover what is causing the destruction of oil rigs off the coast of Scotland.