After being fatally wounded by a CyberMondan on Floor 1056 of a Mondasian colony ship, the Twelfth Doctor began to hold back his regeneration as he battled against the Exodus Cyberman, and continued to resist the change of appearance due to his refusal to "keep on being somebody else", (TV: The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).) having grown tired of outliving everyone he held dear. However, after a final adventure against the Testimony Foundation with his first incarnation during his own regeneration crisis, the Doctor accepted that the universe would "get it all wrong without [him]" and allowed himself to regenerate in his TARDIS. (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).)
History[]
Anticipation[]
When the Twelfth Doctor broke his toe, Clara Oswald suggested that he regenerate to heal the injury, but he berated the idea as a waste. (PROSE: The Blood Cell [+]James Goss, BBC New Series Adventures (BBC Books, 2014).)
When threatened by Captain Lundvik, the Doctor told her she would have to shoot him, Clara and Courtney Woods, but warned that she would "have to spend a lot of time shooting [him] because [he would] keep on regenerating." Clara, during a falling out with the Doctor, later threatened to "smack [him] so hard [he would] regenerate". (TV: Kill the Moon [+]Peter Harness, Doctor Who series 8 (BBC One, 2014).)
While suffering from the common cold, the Doctor, overreacting to the illness, considered the possibility of needing to regenerate. (COMIC: The Day at the Doctors [+]Colin Bell, DW12 backup comic stories (Titan Comics, 2016).)
When the Doctor confronted Rassilon in Gallifrey's Drylands after escaping from his confession dial, Rassilon contemplated using his gauntlet to force the Doctor to regenerate as a method of torture, rhetorically wondering how many regenerations the Doctor had been granted, but was interrupted before he could attack the Doctor with the gauntlet. (TV: Hell Bent [+]Steven Moffat, Doctor Who series 9 (BBC One, 2015).)
The Doctor was forced through seven false regenerations by a "regeneration vampire". With the assistance of his eleventh incarnation, the regeneration energy he expended was returned to him. (AUDIO: Regeneration Impossible [+]Alfie Shaw, Short Trips (Big Finish Productions, 2020).)
The Doctor fakes a regeneration. (TV: The Lie of the Land [+]Toby Whithouse, Doctor Who series 10 (BBC One, 2017).)
After the Monk invasion, the Doctor needed to know if Bill Potts was under the control of the Monks, and deceived her into shooting him in a rage to see if she had succumbed to the mind control, secretly putting blanks in all the guns, and faking his regeneration to complete the illusion. He made it look like the process had started, but emerged as himself to show her that he had deceived her. (TV: The Lie of the Land [+]Toby Whithouse, Doctor Who series 10 (BBC One, 2017).)
When making his case for entering the dimension of the light-eating locusts to prevent them breaking through a inter-dimensional temporal rift, the Doctor noted that he would regenerate if the light-eating locusts killed him. (TV: The Eaters of Light [+]Rona Munro, Doctor Who series 10 (BBC One, 2017).)
After the Doctor was captured by the Saxon Master and Missy on a Mondasian colony ship, they debated throwing him off a hospital roof to kill him, but decided against it when they realised their uncertainty on how many regenerations he had remaining, believing they "could [be] up and down the stairs all night." (TV: The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).)
The cause[]
Having altered the Master's programming on what the Cybermen could convert before he was captured, the Twelfth Doctor was freed by Missy when he convinced her he could hold back the advancing Cyber-Army, and summoned Nardole and a shuttlecraft he had found to collect them from the hospital roof, but, as Missy and the Master made their escape to the shuttlecraft, the Doctor was grabbed by a CyberMondan while he was distracted giving instructions and electrocuted to a fatal degree until he was saved by Bill Potts overcoming her Cyber-conversion programming enough to destroy the attacking Cyberman. After the Doctor lost consciousness from his injuries, Bill picked him up as the shuttlecraft flew through the colony ship to Floor 0507, where Bill lost consciousness for two weeks as the Doctor, having started to regenerate, prepared the farmers on Floor 0507 for an attack by the Cybermen with Nardole, while the Master and Missy looked for an escape route off the ship. The Doctor continued to hold off the regeneration energy from causing his change of appearance as he helped Bill come to terms with her Cyber-conversion, until Missy accidently alerted the Cybermen on Floor 1056 to their location by activating the lift to Floor 0000.
The Doctor is struck down by the Cybermen. (TV: The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).)
Knowing that the farmers stood no chance against the Weapons-grade Cybermen created by Operation Exodus, the Master and Missy opted to flee as the Doctor, Bill and Nardole prepared an evacuation plan to Floor 0502, with the Doctor ordering Nardole to lead the farmers to safety while he fought the Cybermen as a distraction, with Bill opting to stay and help the Doctor as a form of revenge on the Cybermen for her conversion. When the Cybermen finally arrived, Nardole led the farmers to the lift to start the evacuation, with Bill and the Doctor separating the cover more ground, knowing that their situation was "without hope", but opting to give their lives "without witness [and] without reward". The Doctor soon found a platoon of Exodus Cybermen and used his sonic screwdriver to set of a series of explosions to destroy the Cybermen while recounting his previous victories of them, until he was struck down by a Mondasian Cyberman. No longer able to hold back his regeneration, the Doctor decided to denoted an explosion that engulfed the whole area he was in, destroying the Cybermen, but damaging himself to severely to regenerate, causing him to pass just before Bill arrived at his side. (TV: The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).)
State of grace[]
As Bill cried over the Doctor's body, Heather answered the call of her tears and removed Bill from her Cyber-body by turning her into Sentient oil, and the pair returned the Doctor to his TARDIS so he could "rest in peace", with Bill kissing his cheek before she and Heather left to see the universe, with her kiss reactivating the regeneration process and causing the Doctor to burst back to life, muttering the final words from his previous three regenerations. However, tired of "being someone else", the Doctor refused to regenerate as the TARDIS landed in the South Pole, (TV: The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).) with the Doctor stepping outside as he was overcome with regeneration energy (TV: World Enough and Time [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).) that he was able to hold back as he was approached by the First Doctor (TV: The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017).) going through his own "state of grace" before his regeneration.
The Doctor tells Bill's Glass avatar that he wants to rest. (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).)
As the two Doctor summarised their situation, they were found by Captain Archibald Hamish Lethbridge-Stewart while he was fleeing the glass avatar of Helen Clay from the Testimony Foundation trying to return him to his death in Ypres during Christmas 1914. After their offering of Bill in exchange for the Captain aroused his suspicions of their intent, the Twelfth Doctor took his TARDIS team to Villengard to consult the Dalek Pathweb with Rusty, only to learn that the Testimony Foundation had the benevolent mission of collecting the memories of the deceased as a way of learning from them, just as Bill revealed she was a glass avatar and explained that the two Doctor refusing to regenerate at the same time had caused the Captain's return to his death malfunction. Feeling responsible, the Twelfth Doctor requested to return the Captain personally, but his despair at not being able to see his family at Christmas inspired the Doctor to alter the timeline so that he and an enemy soldier were saved by the 1914 Christmas truce, with his act of kindness helping the First Doctor to face his regeneration as he returned to his TARDIS. As he sat alone on the battlefield, the Doctor was joined by glass avatars of Bill and Nardole, who, after restoring his erased memories of Clara Oswald as a "goodbye present", encouraged him to keep living because "everybody in the universe might just go cold" if he died, with the Doctor protesting that his long life had become "a battlefield" left empty "because everyone else [had] fallen". As they enjoyed a final embrace before the glass avatars returned to the Testimony Foundation, the Doctor decided it was "time to leave the battlefield". (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).)
The regeneration[]
As he thought of his past companions, (POEM: Friend Ship [+]Error: Code 2 - no data stored in variables, cache or SMW.) the Doctor activated the TARDIS scanner to get a look at "the silly old universe" as he conceded that he needed to regenerate because the universe would "get it all wrong without [him]." After providing advice to his next incarnation about never being cruel or cowardly, how "hate [was] always foolish, and [that] love [was] always wise", never to fail at being at kind as they laughed hard and ran fast, the Doctor regenerated in an explosive fashion. (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).)
As they regenerated, the new Doctor relived memories from each of their past lives while the Twelfth Doctor continued to give advice, recalling the magnificence of their TARDIS, (COMIC: The Many Lives of Doctor Who [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) their first human companions Ian Chesterton and Barbara Wright, (COMIC: The Path of Skulls [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) the strangeness of some of their adventures, (COMIC: Card Conundrum [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) their love for London (COMIC: Invasion of the Scorpion Men [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) and for parts of Earth outside the UK, such as New York City. (COMIC: Time Lady of Means [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) As the Thirteenth Doctor began to materialise as the new body (COMIC: The Many Lives of Doctor Who [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) and became a a certainty instead of a possibility, her actualised potential sent postcards to various friends as a "hello to the world", including V. M. McCrimmon and Grandfather Halfling in the City of the Saved (PROSE: Postscript [+]Error: Code 2 - no data stored in variables, cache or SMW.) and Alistair Gordon Lethbridge-Stewart during his later years. (PROSE: The HAVOC Files 4 [+]Error: Code 2 - no data stored in variables, cache or SMW.) As the Twelfth Doctor informed the Thirteenth Doctor of her not actually being their thirteenth incarnation, (COMIC: The Many Lives of Doctor Who [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) they remembered Gallifrey and the regeneration limit, (COMIC: Ophiuchus [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) how the Sixth Doctor felt so different to the Fifth Doctor after the Fifth Doctor's regeneration, (COMIC: Virtually Indestructible [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) the fact that the Master always found a way to survive beyond death, (COMIC: Crossing the Rubicon [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) how things were not always as they appeared (COMIC: The Time Ball [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) and the Last Great Time War. (COMIC: The Whole Thing's Bananas [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).)
The Thirteenth Doctor nears the end of her regeneration. (COMIC: The Many Lives of Doctor Who [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).)
As the regeneration finished, the Doctor noticed that her clothes no longer fitted and felt "there was something different about this body". (PROSE: Twice Upon a Time [+]Paul Cornell, adapted from Twice Upon a Time (Steven Moffat), Target novelisations (Target Books, 2018).) After the Twelfth Doctor's ring fell off her finger, (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).) the Doctor remembered how the Ninth Doctor had to relearn to be "the Doctor" after the Time War, (COMIC: Return of the Volsci [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) how the Tenth Doctor helped Elizabeth Garrett Anderson become the first female doctor in England, (COMIC: Nurse Who? [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) her wife River Song, (COMIC: Without a Paddle [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) and how the Daleks were a constant threat throughout her life. (COMIC: Harvest of the Daleks [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) As the Twelfth Doctor felt he nothing left to help her with, (COMIC: The Many Lives of Doctor Who [+]Richard Dinnick, The Many Lives of Doctor Who (Titan Publishing Group, 2018).) the Thirteenth Doctor caught her reflection in the TARDIS scanner and deemed her new body to be "brilliant". (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).)
Immediate aftermath[]
Info from Things She Thought While Falling [+]Chris Chibnall, Doctor Who: Lockdown! (Doctor Who website, 2020)., The Woman Who Fell to Earth [+]Chris Chibnall, Doctor Who series 11 (BBC One, BBCA, Space and Australian Broadcasting Corporation, 2018)., The Ghost Monument [+]Chris Chibnall, Doctor Who series 11 (BBC One, 2018)., and First Day of the Doctor [+]Paul Lang, Doctor Who The Official Annual 2024 (Penguin Group, 2023). needs to be added
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