Planet of Evil is the second serial of the 13th season of the British science fiction television series Doctor Who. It was first broadcast in four weekly parts on BBC1 from 27 September to 18 October 1975.

The thirteenth season of British science fiction television series Doctor Who began on 30 August 1975 with the story Terror of the Zygons, and ended with The Seeds of Doom. This is the second series to feature the Fourth Doctor, played by Tom Baker, with Philip Hinchcliffe producing and Robert Holmes script editing. In September 2009, it was ranked as readers' favourite season in Doctor Who Magazine issue 413.