"The End of Time" is a two-part story of the British science fiction television series Doctor Who, originally broadcast in the United Kingdom on BBC One on 25 December 2009 (Part 1) and 1 January 2010 (Part 2). It is the fifth Doctor Who Christmas special and the last entry in a series of specials aired from 2008 to 2010. It marks the final regular appearance of David Tennant as the Tenth Doctor and introduces Matt Smith[1] as the Eleventh Doctor. At the time, it was the last Doctor Who story written and produced by Russell T Davies,[2] who shepherded the series' return to British television in 2005 and served as the series's executive producer and chief writer, until he returned to the position in 2022 for the 60th anniversary specials onwards.[1][3][4]
Bernard Cribbins, who appeared in the story "Voyage of the Damned" and throughout Series 4 as Wilfred Mott, grandfather of Donna Noble, acts as the companion to the Doctor in this two-part story.[5] The special also features the return of many other actors to the show, including Catherine Tate, John Simm, Jacqueline King, Alexandra Moen, Billie Piper, Camille Coduri, Freema Agyeman, Noel Clarke, John Barrowman, Elisabeth Sladen, Tommy Knight, Jessica Hynes and Russell Tovey.
The story features the Tenth Doctor (Tennant), who has been running from a prophecy of his impending demise, as he is drawn into a scheme by his old nemesis, the Master (Simm). The Master brings the human race under his control as part of an elaborate plan to restore the world of his and the Doctor's own people, the Time Lords, from their demise in the Time War referred to in the series. The Doctor is able to avert this, but incurs fatal injuries. In the episode's conclusion, as has happened before, the Doctor regenerates and becomes a new man with a new personality and physical traits, setting up the show's following series with Matt Smith as the Eleventh Doctor and Steven Moffat as executive producer.
The Ood warn the Tenth Doctor that the Master has returned, heralding "the end of time". On Earth, a cult resurrects the Master, but his widow Lucy sacrifices herself to sabotage the ceremony. The Master is returned to life with incredible strength, but is plagued by constant hunger and suffers from slow degeneration. The Doctor encounters Wilfred, who helps track down the Master's location. The Doctor fears a prophecy stating "he will knock four times', which will result in the Doctor's death. He discovers that the drumbeat noise in the Master's head was externally implanted. The Master is taken into the custody of billionaire Joshua Naismith, whom the Doctor recognizes from the Ood's vision. Naismith has recovered a broken Vinvocci medical device and wants the Master to repair it. At Naismith's mansion, the Master reprograms the device to change humanity into six billion clones of himself. Wilf shields himself in a control room to avoid being changed, and his granddaughter Donna also doesn't change due to her biology being rewritten in Journey's End, but does not remember this due to the Doctor being forced to wipe her memories of him to protect her. The Doctor and Wilfred take refuge from the Masters on the Vinvocci salvage ship.
On the last day of the Time War, faced with the destruction of Gallifrey and the end of his race, the Time Lord President Rassilon implants the drumbeat in the Master's head as a child in a desperate bid to escape the "Time Lock" in which the Time Lords are trapped. In the present, the billions of Masters amplify that drumbeat signal. Still needing a contact point, Rassilon launches a Gallifreyan diamond to Earth. The Master uses it to create a link that brings Gallifrey out of the Time War and into orbit around Earth. Twisted by the horrors of the Time War, Rassilon plans for the Time Lords to ascend to an incorporeal state while destroying the rest of creation. He stops the Masters plan of implanting himself into the Time Lords by restoring the human race. The Doctor returns to Naismith's mansion armed with Wilfred's gun, taking aim at both the Master and Rassilon. Each encourages the Doctor to kill the other. He tells the Master to move and destroys the diamond, severing the link with Gallifrey. Rassilon, determined to drag the Doctor back to the Time War with him is stopped by the Master, and both disappear into the rift.
Stunned to be alive, the Doctor then hears four knocks. He discovers that Wilfred had come to help, but is trapped in one of the control rooms of the Vinvocci device that is about to be flooded by radiation. The Doctor saves Wilf by taking his place in the control room, and his regeneration is triggered by the radiation poisoning. After returning Wilfred home, the Doctor visits his past companions: he saves Martha and Mickey, now married, from a Sontaran; prevents Luke Smith from being hit by a car and bids farewell to Sarah Jane; connects Jack with former midshipman Alonso Frame; meets Joan Redfern's great-granddaughter and inquires if she led a happy life; sees Wilf one more time to give him a winning lottery ticket for Donna as her wedding present; and briefly encounters Rose the year she is due to first meet the Ninth Doctor. He sets the TARDIS in flight and regenerates into the Eleventh Doctor, causing an explosion that makes the TARDIS begin crashing back down to Earth.