While travelling, typically with companions, the Doctor works to save lives and liberate oppressed peoples by combating various enemies.
Tennant and Davies departed following a series of specials, replaced by Matt Smith as the Eleventh Doctor and Steven Moffat as showrunner, respectively.
Capaldi was replaced by Jodie Whittaker, the first woman to play the role, as the Thirteenth Doctor; Chris Chibnall became showrunner.
[18] In his last story, "The Parting of the Ways", the Doctor absorbed the Time Vortex to save his companion, leading to his regeneration.
A loose story arc deals with the consequences of the Time War and its impact on the Doctor, and the mystery of the seemingly omnipresent phrase 'Bad Wolf'.
[24] With the success of the first series, Doctor Who returned to its old formula of visiting alien planets in addition to time travel.
[25] Tennant retained the role until Part Two of "The End of Time" when the Doctor suffers radiation poisoning, saving his companion.
[28] From "School Reunion" through "The Age of Steel", Noel Clarke, who recurred in series 1, appeared as companion Mickey Smith.
[31][32] In this series, Catherine Tate reprises her role as Donna Noble from "The Runaway Bride", this time as a full-fledged companion.
The first part "The Stolen Earth" brings back all the long-term companions in the revived series up to that moment for the finale.
[41] This series introduces Karen Gillan and Arthur Darvill as companions Amy Pond and Rory Williams respectively.
[42][43] It deals with cracks spreading throughout time and space erasing things from existence; the opening of the "Pandorica" is also mentioned in various episodes.
The original transmission of series 6 was split into two parts, with the first seven episodes airing April to June 2011 and the final six from late August to October 2011.
It deals with the exit of the Ponds midway through the series in "The Angels Take Manhattan", and the mystery of the new companion Clara Oswald portrayed by Jenna Coleman.
It deals with the "prophecy of the Hybrid", and the consequences of the changing dynamics of the Doctor and Clara's relationship, which leads to her departure in the finale "Hell Bent".
[58] This season introduces Pearl Mackie and Matt Lucas as the Doctor's new companions Bill Potts and Nardole respectively, both of whom depart in the series's corresponding Christmas special "Twice Upon a Time".
[63] The series introduces Mandip Gill, Bradley Walsh and Tosin Cole as the new companions Yasmin Khan, Graham O'Brien and Ryan Sinclair respectively.
It involves a universe-ending anomaly, called the "Flux", which leads to several enemies separately attempting to take over Earth and destroy most of the universe.
[11] Millie Gibson will return as Ruby Sunday, alongside new companion, Belinda Chandra, played by Varada Sethu.