The Sea Devils is the third serial of the ninth season of the British science fiction television series Doctor Who, which was first broadcast in six weekly parts from 26 February to 1 April 1972. It was written by Malcolm Hulke and directed by Michael E. Briant. The story is the first appearance of the Sea Devils.
In the serial, the Doctor (Jon Pertwee) and his assistant Jo Grant (Katy Manning) visit the Doctor's nemesis the Master (Roger Delgado) in his island prison and encounter the Sea Devils, the aquatic cousins of the Silurians.
Malcolm Clarke's incidental music for this story was notably more experimental than the show's usual scores by Dudley Simpson, being entirely electronic, created on the Radiophonic Workshop's EMS Synthi 100 synthesizer. He also found time to appear in the 1979 documentary The New Sound Of Music with a trusty Synthi 100!
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