Doctor Who (1963–1989)
4 user 2 critic

The Sea Devils: Episode One 

The Doctor and Jo visit the Master at his island prison where the Doctor becomes curious about a number of ships sinking in the area.


Michael E. Briant (as Michael Briant)


Malcolm Hulke (by)

On Disc

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Episode complete credited cast:
Jon Pertwee ... Doctor Who
Roger Delgado ... Master
Katy Manning ... Jo Grant
Edwin Richfield ... Captain Hart
Clive Morton ... Trenchard
Royston Tickner Royston Tickner ... Robbins
Neil Seiler Neil Seiler ... Radio Operator
Declan Mulholland Declan Mulholland ... Clark
Hugh Futcher ... Hickman
June Murphy June Murphy ... 3rd Officer Jane Blythe
Alec Wallis Alec Wallis ... Ldg. Telegraphist Bowman
Brian Justice Brian Justice ... Castle Guard Wilson
Terry Walsh ... Castle Guard Barclay
Pat Gorman ... Sea Devil


The Doctor and Jo visit the Master at his island prison where the Doctor becomes curious about a number of ships sinking in the area.

Plot Summary | Add Synopsis


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Release Date:

26 February 1972 (UK) See more »

Company Credits

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Technical Specs

Sound Mix:




Aspect Ratio:

1.33 : 1
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Did You Know?


The script called for Jo Grant and the Doctor to climb up a ladder to get into a sea fortress. The ladder proved too slippery for Katy Manning, so stuntman Stuart Fell did the shot dressed as Grant. See more »


The door to The Master's "cell" is fully riveted, indicating that it's supposed to be solid steel, however given the way it handles and the sound it makes on closing, it's clearly a wooden door painted to look oxidised. See more »

Crazy Credits

The BBC wish to acknowledge the help given to them by the Royal Navy in the making of this programme See more »


Featured in Musical Scales (2008) See more »

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User Reviews

Great example of Pertwee era 'monster threatens the Earth' format.
29 September 2014 | by A_Kind_Of_CineMagicSee all my reviews

Review of all 6 episodes:

The Master teams up with reptilian creatures who have been dormant under the ocean for millions of years to try to conquer humanity (again). These creatures, which are dubbed Sea Devils by terrified humans, are relatives of the 'Silurians' or as The Doctor re-names them Eocenes. They were on Earth before humans and want to claim the planet back after eons of suspended animation in the ocean depths. The Doctor tries to broker peace whilst The Master whips up a war. Human leaders also have the appetite for war so trapping The Doctor in the middle.

This adventure is not flawless but provides superb entertainment and iconic scenes throughout. The first two episodes and last two episodes of this adventure are terrific fun, exciting, interesting, well written and acted with only very minor faults. Whilst the middle two parts are slightly more flawed as the story is marginally stretched over 6 parts, they too are really good. The interest and quality levels never drop below 9/10 and this epitomises Pertwee era Who.

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