Doctor Who: Robot, Episode 1 on AllMovie

In the final episode of Doctor Who's 11th season, the Doctor endured a crisis of conscience, one so profound that he was forced into another of his periodic regenerations. In this way, Jon Pertwee was able to leave the series, to make way for the Fourth Doctor, who in turn was unveiled in the 12th-season opener, episode one of "Robot" (which was also the first of the series' story continuities to be shot completely on videotape, with no filmed sequences). Tom Baker took over the role of the Doctor, spending the bulk of the episode getting accustomed to his new body. While resting from his labors, the new Doctor falls asleep for a few minutes -- just enough time for a robot to steal the plans for a valuable disintegrator gun, thereby setting the plot proper in motion. First telecast on December 28, 1974, the first episode of the four-part "Robot" was written by Terrance Dicks.