"Mission to the Unknown", sometimes known as "Dalek Cutaway", is the only single-episode serial (not counting the 20th anniversary feature-length episode - The Five Doctors) of the original run in the television series Doctor Who. It is a standalone episode, serving as an introduction to the 12 part story The Daleks' Master Plan. It is notable for the complete absence of the regular cast, including the Doctor (although William Hartnell is still credited on-screen). The story focuses on Marc Cory and his attempts to warn Earth of the Daleks' latest plan.
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