The Leisure Hive is the first serial of the 18th season of the British science fiction television series Doctor Who, which was first broadcast in four weekly parts on BBC1 from 30 August to 20 September 1980. It marks the return of John Leeson as the voice of K9.

The Gunfighters is the eighth serial of the third season in the British science fiction television series Doctor Who, which was first broadcast in four weekly parts from 30 April to 21 May 1966.