'The Sea Devils' (6 Parts) Story Code 'LLL' by Malcolm Hulke

The Doctor and Jo visit the Master in his high-security prison on an island off of England's south coast. Colonel Trenchard, the prison governor, tells them that ships have been mysteriously disappearing in the area, and the Doctor decides to investigate. He is told by Captain Hart, the commander of the nearby Naval base, that these disappearances have centred around an abandoned sea fort. Jo and the Doctor visit the fort, and are attacked by man-like marine creatures, nicknamed Sea Devils by one of the fort's crewmen. These creatures are the amphibious cousins of the Silurians, the race of Earth reptiles that the Doctor encountered on Wenley Moor. The Master, aided by a misguided Trenchard, is stealing equipment from the Naval base, so that he can construct a machine to awaken the remaining Sea Devils from their hibernation, and use them in his plans to conquer the planet. The Doctor travels to the Sea Devils' base in a diving bell, in order to achieve a peaceful solution to their attacks, but the creatures capture him. Walker, a pompous politician, orders a depth charge attack on the Sea Devils' base, and in the confusion, the Doctor manages to escape back to the surface in a captured submarine. The Sea Devils attack and capture the Naval base, and the Master forces the Doctor to help to complete work on the revivication machine. But the Doctor sabotages the machine, and he and the Master escape just as the Sea Devils and their base are destroyed by the resulting the explosion.

Jon Pertwee (Doctor Who), Katy Manning (Jo Grant), Roger Delgado (Master), Edwin Richfield (Captain Hart), Clive Morton (Trenchard), Royston Tickner (Robbins) , Neil Seiler (Radio Operator) , Declan Mulholland (Clark), Hugh Futcher (Hickman) , June Murphy (3rd Officer Jane Blythe), Alec Wallis (Ldg. Telegraphist Bowman), Brian Justice (Castle Guard Wilson) , Terry Walsh (Castle Guard Barclay), Pat Gorman (Sea Devil), Eric Mason (C.P.O. Smedley), Donald Sumpter (Commander Ridgeway), David Griffin (Lt. Commander Mitchell), Christopher Wray (Ldg. Seaman Lovell), Stanley McGeagh (Castle Guard Drew), Colin Bell (C.P.O. Summers), Brian Vaughan (Lt. Commander Watts), Rex Rowland (A/B Girton), Martin Boddey (Walker), Norman Atkyns (Rear Admiral), Peter Forbes-Robertson (Chief Sea Devil), John Caesar (C.P.O. Myers)

Produced by Barry Letts
Directed by Michael Briant

TX:
Part 1 - 26th February, 1972 @ 5.50pm - 6.15pm
Part 2 - 4th March, 1972 @ 5.50pm - 6.15pm
Part 3 - 11th March, 1972 @ 5.50pm - 6.15pm
Part 4 - 18th March, 1972 @ 5.50pm - 6.15pm
Part 5 - 25th March, 1972 @ 5.45pm - 6.10pm
Part 6 - 1st April, 1972 @ 5.50pm - 6.15pm

Notes:
*Featuring the Third Doctor, Jo, the Brigadier and UNIT

*First appearance of the Sea Devils

*The Master watches a clip from the childrens programme 'The Clangers' (from the episode 'The Rock Collector') in Part 1, believing it to be a documentary

*Working title: 'The Sea Silurians'