Chief Sea Devil (Doctor Who and the Sea-Devils)

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According to one account, a Sea Devil took over as Chief Sea Devil of the colony who awoke in the 1970s, shortly before its destruction, following the death of his predecessor.

He refused to honour his predecessor's agreement with the Master, double-crossing him. (PROSE: Doctor Who and the Sea-Devils) According to another account, it was the original Chief Sea Devil who turned on the Master. (TV: The Sea Devils) Ultimately, the whole Sea Devil colony was killed by the device which the Master had built to awaken those still in hibernation, which the Doctor had rigged to explode instead. (TV: The Sea Devils, PROSE: Doctor Who and the Sea-Devils)