<span class="SFPTagline"> From SCIFIPEDIA </span>

Doctor Who, Season 21 was to be a season of change. Lead actor Peter Davison, fearing typecasting and remembering advice from former Doctor Who lead Patrick Troughton, had decided that three years was enough. As such, he indicated to the production team that this season would be his last. Aware of Davison's intentions, companions Janet Fielding (Tegan) and Mark Strickson (Turlough) had decided that it might also be time for them to depart. Furthermore, it was decided that the robotic companion Kamelion was far too problematic to operate and should be dispensed with. This necessitated the creation of a new companion character and the casting of a new incarnation of the Doctor.

The new companion would be American college student Perpegilliam "Peri" Brown, played with a usually accurate, but far from perfect, American accent by British actress Nicola Bryant.

For the new Doctor, the production team decided that in order to contrast with Peter Davison's kind, soft-spoken protagonist, the new Doctor would be fiery, flamboyant, and even initially a bit dislikable. This was intended to be the beginning of a long character arc. The new Doctor would slowly evolve into a more positive force over several seasons. Actor Colin Baker was cast in the role and, in an unusual move, would debut in the season's final story rather than at the beginning of the following season.

As for the actual stories, this season is notable for the return, after a long absence of frequent foes the Daleks and a return teaming of two reptilian races that hadn't apeared since the early seventies: the Sea Devils and the Silurians. However, it is the return of a writer that is most noteworthy. "The Caves of Androzani" was the first story from master Doctor Who scribe Robert Holmes since season 16. Easily among the most popular stories of the entire classic series, it served as Peter Davison's swansong. The actor would later comment that he would have stayed longer if he'd had more stories of that quality.

The season began airing on January 5, 1984.

• "Warriors of the Deep" (4 episodes)
• "The Awakening" (2 episodes)
• "Frontios" (4 episodes)
• "Resurrection of the Daleks" (2 double-length episodes)
• "Planet of Fire" (4 episodes)
• "The Caves of Androzani" (4 episodes)

(Colin Baker assumes the title role)

• "The Twin Dilemma" (4 episodes)