Overview
The Mind Robber is the second serial of the sixth season of the British science fiction television series Doctor Who, which was first broadcast in five weekly parts from 14 September to 12 October 1968.
The serial is set outside of time and space in a world where fictional characters and mythological creatures including Medusa and the Minotaur exist. In the serial, the English fiction writer "the Master" (Emrys Jones) tries to recruit the time traveller the Second Doctor (Patrick Troughton) to replace the Master's role as the creative power in this realm because of the Master's advancing age.
Plot
After defeating the Dominators and starting off a volcanic eruption, the Doctor, Jamie and Zoe find themselves and the TARDIS in the path of a lava flow. Upon trying to dematerialise out of the way, the TARDIS experiences a fault in the fluid link. At the insistence of Zoe and Jamie, the Doctor uses an emergency unit that takes the TARDIS into another dimension outside of reality. Upon their arrival into an empty white void, the travellers find themselves assaulted, first subtly then overtly, by an unseen force. The attack results in the TARDIS breaking apart and the travellers being scattered.
The Doctor, after experiencing a series of curious encounters, manages to find Jamie and Zoe. He soon deduces that they are in a world filled with fictional and mythological characters. They finally meet a person called "The Master" who seems to be in charge. It turns out that he is in fact an Earth man abducted and brought to the land of fiction in order to provide creative energies for the unseen aliens who are really in charge. Everything that the Doctor has experienced was a series of tests to prepare him for his role as replacement. The aliens' plan is to control everyone on Earth and bring them to the land of fiction, leaving the Earth itself empty for easy colonisation.
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