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John Wiles was credited on four Doctor Who serials: "The Daleks' Master Plan" (1965-1966), "The Power of the Daleks" (1966), "The Evil of the Daleks" (1967), and "The Dalek Invasion of Earth" (1964). He played the role of Dalek operator Dortmun in all four serials, and his distinctive voice and mannerisms helped to make the Daleks one of the most iconic monsters in television history.