Last updated 24 March 2024


Episode Five

Series Episode Number: 316

World Premiere: Sat 25 Mar 1972 - 5:45pm BST [BBC One] (United Kingdom)
First Broadcast: Fri 21 Nov 1975 - 6:30pm CST [WTTW 11 Chicago]
Running Time: 24 minutes 53 seconds

8.30 Million (UK)


Chart Position: 39 () (UK)

Recorded on Mon 13 Dec 1971 in TC8
Archive State: PAL 2 VT



The Doctor is captured by the Sea Devils and taken to their undersea base. There he tries to make peace with the creatures, but his efforts are thwarted by the Navy.


Characters hide uncredited
Doctor WhoJon Pertwee
MasterRoger Delgado
Jo GrantKaty Manning
Captain HartEdwin Richfield
Commander RidgewayDonald Sumpter
Lt. Commander MitchellDavid Griffin
C.P.O. SummersColin Bell
Ldg. Seaman LovellChristopher Wray
A/B GirtonRex Rowland
WalkerMartin Boddey
Rear AdmiralNorman Atkyns
3rd Officer Jane BlytheJune Murphy
Ldg. Telegraphist BowmanAlec Wallis
Chief Sea DevilPeter Forbes-Robertson
Sea DevilPat Gorman
Stunt ManTerry Walsh (uncredited)
Stunt ManStuart Fell (uncredited)
Stunt ManMike Horsburgh (uncredited)
Stunt ManPeter Brace (uncredited)
Stunt ManMarc Boyle (uncredited)
Stunt ManMike Stephens (uncredited)
Sea DevilBryan Nolan (uncredited)
Sea DevilSteve Ismay (uncredited)
Sea DevilGeoffrey Witherick (uncredited)
Sea DevilFrank Seton (uncredited)
Submarine RatingDennis Plenty (uncredited)
Submarine RatingRon Tingley (uncredited)