Parts: 4
Writer: Robert Holmes
Airdates: 3 January 1970 - 24 January 1970
Production Code: AAA
Creature Feature: Nestene and Autons
Special Guests: UNIT (the Brigadier)
Story: A group of meteorites descends upon Essex - and not only do they land safely, they do so through a superheated tunnel of air. The Brigadier suspects something unusual, so he recruits scientist Elizabeth Shaw, a specialist in meteorites, from Cambridge. She discovers that the meteorites are actually hollow spheres made of plastic, and they appear artificially-made. The Brigadier wishes that the Doctor were present.
And indeed, the TARDIS has arrived on Earth, but its occupant is unconscious. The Doctor is serving sentence from the Time Lords - a forced regeneration and exile to Earth in the twentieth century. By the time the Doctor gets over his post-regeneration weakness and convinces the Brigadier that he is who he claims, dangerous things are beginning to happen.
Key government figures are being replaced by plastic dummies, and blank-faced mannequins with guns concealed in their hands are rampaging around the countryside. Unless the Doctor and Liz can infiltrate Auton Plastics and discover its deadly secret, an alien consciousness will conquer the entire Earth.