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Twice Upon a Time was the 2017 Christmas Special of Doctor Who. It was the show's thirteenth Christmas special since its revival and the fourth starring Capaldi as the Doctor. It was also the final chronological appearance of Peter Capaldi as the Twelfth Doctor and introduced Jodie Whittaker as the Thirteenth Doctor in its closing moments.

After a surprise appearance at the end of The Doctor Falls [+]Steven Moffat, Doctor Who series 10 (BBC One, 2017)., the First Doctor was an integral part of the special's narrative. Here, he was portrayed by David Bradley, who had previously played the original actor William Hartnell in An Adventure in Space and Time. Archival footage from The Tenth Planet [+]Kit Pedler and Gerry Davis, Doctor Who season 4 (BBC1, 1966). was used to bookmark the First Doctor's place in this story, with Twice Upon a Time retroactively inserting one final adventure for the First Doctor before his regeneration, as well as explaining his absence after leaving Ben and Polly during the last episode of The Tenth Planet.

Speaking of which, Ben Jackson and Polly Wright made a brief re-reappearance in the programme for the first time since their exit in 1967's The Faceless Ones. Bill Potts joined the two Doctors as a Testimony glass avatar. Past companions Nardole and Clara Oswald made similar brief appearances. Rusty, from Capaldi's second episode, Into the Dalek [+]Phil Ford and Steven Moffat, Doctor Who series 8 (BBC One, 2014)., made his second appearance in Villengard, a location mentioned only once before on television, in Steven Moffat's second television story, 2005's The Doctor Dances [+]Steven Moffat, Doctor Who series 1 (BBC One, 2005)..

It's also worth noting that Twice Upon a Time marks the first time two different incarnations of the Doctor were seen regenerating in the same episode; with the First Doctor's regeneration into the Second Doctor shown briefly before the special ends with the Twelfth Doctor regenerating.

In early 2018, Murray Gold announced his departure from Doctor Who after twelve years at the Gallifrey One convention, confirming that Twice Upon a Time was his last episode. It was also the final story with Steven Moffat as head writer and the first to include any part written and overseen by incoming lead writer, Chris Chibnall.[1]

While not known at the time, this would also turn out to be the last consecutive Christmas special of the revived series, breaking the streak that began with The Christmas Invasion [+]Russell T Davies, Doctor Who Christmas special (BBC One, 2005). in 2005. The show would forgo its usual Christmas special in 2018 in favour of a New Year Special at the beginning of 2019. The New Year's Day broadcasts continued from 2019 to 2022, before Christmas specials returned with The Church on Ruby Road [+]Russell T Davies, Doctor Who Christmas Special 2023 (BBC One and Disney+, 2023)., which aired on 25 December 2023.


As the Doctor nears regeneration, he stumbles on his original self, also refusing to change. It takes a captain, a glass avatar and a familiar face to convince the Doctors the universe still needs them.


The First Doctor nears his end after an encounter with Mondasian Cybermen. He is freed from his restraints by his companions Ben and Polly, now that the threat is over. However, he is weak, his body beginning to regenerate. Refusing to give in, the Doctor leaves and wanders the South Pole, mumbling to himself that he will not change out of cowardice. Nearing his TARDIS, he hears a voice in the distance yelling in defiance. Seeing a figure kneeling outside his TARDIS, the Doctor asks who the man is. The man claims to be the Doctor. With a smug sense of superiority, the First Doctor tells the man that's not true; "you may be a doctor, but I am the Doctor. The original, you might say."

The scene transitions to the Twelfth Doctor as he gets to his feet, shocked to see his past self. The Doctor is at first delighted at meeting his first incarnation, until he realises something isn't right and where the TARDIS has actually landed: the TARDIS has taken him back to the moment of his first regeneration, however, like the Twelfth Doctor, the First Doctor is refusing to regenerate; this causes panic in the Doctor as he doesn't remember refusing to regenerate the first time or remember meeting himself in his current incarnation. The First Doctor is confused and dismisses his future self as just another Time Lord; he asks if he has come to take back "the ship". The Twelfth Doctor laughs in amusement that his original incarnation still calls the TARDIS "the ship".

The First Doctor then asks what the Twelfth has done to the TARDIS, as it's bigger than it used to be. The Twelfth Doctor tells him its from "all those years of being bigger on the inside. You try sucking your tummy in that long", defending his beloved vessel. The Twelfth Doctor questions why his younger self is refusing to regenerate, with the First Doctor lying, claiming he has the courage, and more importantly the right to live and die as he is now. The Twelfth Doctor tells him it's already too late, explaining to the First Doctor that moments ago he was weak but is now suddenly fine, the First as well as the Twelfth Doctor are currently in a "state of grace" but that it won't last forever as both Doctors need to make a choice: choose to regenerate and continue with their lives, or die as they are now. A dreadful realisation suddenly hits the Twelfth Doctor: if his first incarnation refuses to regenerate and dies instead of continuing to live, then all of the things he would do in the future would never happen. However, as the Twelfth Doctor tries explaining this realisation to the First Doctor, as he fears what consequences this decision might cause, the snow around them suddenly freezes in mid-air, capturing the pair's attention, as a man dressed in World War I attire approaches them. He seems disorientated and asks the pair if either of them are a doctor. Exchanging a glance with the First Doctor, the Twelfth asks if the man is making some sort of joke.

Ypres battlefield

The worn torn battlefield in Ypres, 1914.

On Christmas Day 1914, the soldier, a captain in the British Expeditionary Force, lies in a shell hole on the battlefield in Ypres. His revolver is aimed at a German soldier, who also has his sidearm trained on the Captain. Both men realise they will kill each other in self-defence, their respective troops far away in their trenches, unable to assist either of them. Just as the Captain prepares to accept his fate and fire, a wave of energy flows through the field, freezing everything around him. As he exits the hole, he sees a humanoid figure who looks like clear glass standing in front of him. The figure turns to him and a bright light suddenly flashes, encapsulating him. He collapses to the ground in the Antarctic and hearing the two Doctors discussing the static snow, he approaches them.

The scene once more shifts back to the Twelfth Doctor's perspective. A portal of light opens in the distance, and the two Doctors approach it. The First Doctor orders the portal to reveal itself, while the Twelfth Doctor declares that the planet is protected, to the confusion of his first incarnation. However, the light quickly vanishes, surprising the Twelfth Doctor as "that almost never works." The First Doctor returns to the Captain, telling him to enter his TARDIS, and the Twelfth Doctor coaxes him to follow. As they enter, the First Doctor is shocked by the changes to the TARDIS interior, while the Captain is shocked by the room's size. The Twelfth Doctor pulls the monitor over to the First Doctor, telling him his TARDIS is 70 feet away; he then tells him to always remember where he parks as it gets important later. The Captain is taken aback and astonished by the TARDIS.

The First Doctor demands his identity, to which the Twelfth says not to be an idiot as they always know when they meet each other. However, the First Doctor states he does not know, prompting the Twelfth Doctor to show him his hand glowing with regeneration energy. The First Doctor finally realises and accepts that the Time Lord in front of him is indeed the Doctor, his future self, and asks if the Twelfth is his next incarnation, to which the Twelfth says is not the case; he'll become him eventually, "after a few false starts" the Twelfth says with a grin. The First Doctor is confused however, as he thought he would get younger when he regenerated, to which the Twelfth snaps that he is younger than the First Doctor. The Captain interrupts, stating he does not understand what's happening, while examining a VHS tape. The Twelfth Doctor says that's understandable for a soldier from World War I being chased through frozen time by an unknown force. The Captain is at first confused, the Doctor first believes it's because he was able to correctly assume which World War the Captain fought in by looking at his uniform, until the Captain corrects the Doctor, becoming disturbed upon hearing the Doctor refer to the Great War as the first world war rather than just the Great War, the Captain asks the Doctor what he meant by that; the Doctor, realising what he said apologises and simply tells him "spoilers".

The First Doctor notices the Captain's unease, telling the soldier to sit down and orders the Twelfth Doctor to fetch some brandy. He does so, and the First Doctor notices that there is less in the glass than he remembered. The Twelfth Doctor tells him that it's been "rock and roll" over the last 1500 years, so he's entitled to have a glass to steady his nerves. The First Doctor examines the control room, noting that the Twelfth no longer has Polly around since it's so dusty; the Twelfth Doctor begs him to stop saying things like that as it is insulting to women. The First Doctor then notices the Twelfth's electric guitar and amp, which the Doctor tries to pass off as something a companion left behind. However, the First Doctor notes that it is the only thing in the control room that's not covered in dust, making it the Twelfth Doctor's possession.

Suddenly, the TARDIS shakes violently, prompting the Twelfth Doctor to attempt to take off, only to find that the engines are unresponsive. Looking upwards out of the TARDIS doors, he sees large metal claws pulling the TARDIS upwards. Once the TARDIS has stopped moving, the Twelfth Doctor instructs his predecessor to confront their captors. A glass figure seated at the top of a staircase speaks to the Doctor, addressing him as "The Doctor of War." The figure requests the return of the Captain in exchange for a friend of the Doctor. Much to the confusion of the First Doctor, Bill then exits one of the corridors. The Twelfth Doctor quickly exits the TARDIS to hug her, before slowly pulling away, drawing his sonic screwdriver, and scanning Bill. To her surprise, the Twelfth Doctor demands that she proves herself to be real, as he believes Bill to have sacrificed herself to defeat the Cybermen. Bill insists she is her real self, explaining how Heather had saved her. The Twelfth Doctor asks what happened after Heather saved her and where Heather is now. Bill struggles for an answer.

1st sunglasses shock


The Twelfth Doctor decides to confront his captor directly and runs up the staircase. He is slowly followed by his younger self, who questions the need to move so fast. They find an empty chair with several panels behind it. The First Doctor takes to observing the panels, commenting on their extra-terrestrial origin. He turns to his older self, his eyeglass dropping from his eye as he notices the Twelfth Doctor wearing sunglasses to scan the panels. He is utterly perplexed by the idea that the sunglasses are sonic. They turn to the chair, where a woman made completely of glass materialises. While the Twelfth Doctor scans the panels with his sonic screwdriver, the original Doctor looks more closely. He berates the Twelfth Doctor for not noticing the asymmetrical features of the woman's face, blaming his use of the sunglasses instead of his eyes. The Twelfth Doctor shyly agrees, and his younger self throws the sunglasses to the ground.

The Testimony proceeds to explain its desire for the Captain back in exchange for Bill, insisting the Doctors return him to them. The Captain, having heard the conversation, exits the TARDIS. He declares they let him be taken, not wanting any harm to come to Bill because of his cowardice. However, the Twelfth Doctor disagrees. Picking up his sonic sunglasses, he races down the stairs, remarking he will find out what the Testimony's purpose is and he will stop it if he doesn't like it. The First Doctor once more berates him for revealing his plan, stating he hasn't a clue who his future self is supposed to be. The Testimony, in an effort to ruffle the First Doctor, reveals the history he is destined to create as a "Doctor of War" by showing how his future incarnations will engage in various battles, which perplexes him.

12th Bill 1st Captain inside Testimony craft

The Doctors, Bill, and the Captain escape the Testimony

The Twelfth Doctor presses on with his plan to escape, using the sonic screwdriver to activate the crane which pulled the TARDIS up to take them down, the team jumping onto the chains to escape as well. The Testimony refuses to let them escape, halting the chains and pulling the TARDIS back into the ship. However, as they are a safe distance from the ground, the Twelfth Doctor instructs everyone to jump to the ground. Bill expresses concern about what they will do without the TARDIS but the Doctors reveal they have another, younger version at their disposal.

They head to the First Doctor's TARDIS, swiftly entering. As she does so, Bill comments on how much smaller it is, causing the Twelfth Doctor to briefly observe the windows before insisting his younger self take off into "deep space, anywhere". While in flight, the First Doctor insists Bill clean the TARDIS only for the Twelfth Doctor to distract him by pointing out the astral map. The Twelfth Doctor uses the sonic sunglasses to access the data banks noting what his predecessor said earlier before placing the shades on the First Doctor. Befuddled, the First Doctor asks why he must wear them, only for his successor to remark on how much he loves them and tells him to never take them off. The First Doctor asks why there is an option on the glasses called Browser History, causing the Twelfth Doctor to grab the sunglasses and throw them across the TARDIS.

12th 1st Bill Captain in TARDIS Glass on Scanner

The Twelfth Doctor pilots his younger self's TARDIS.

The Twelfth Doctor quickly realises the databanks are rather scarce, given the TARDIS is still young. To compensate, he lands the TARDIS at the centre of the universe, Villengard, impressing his younger self at how easily he did such. While searching the area, the Captain is attacked by a creature with multiple little green legs but they save him, both Doctors recognising the creature as a Dalek mutant. The Twelfth Doctor insists Bill wait in the First Doctor's TARDIS to look after the Captain, but Bill blasts him by calling him a "stupid bloody arse", leading to the First Doctor to threaten her with a "jolly good smacked bottom", much to the Twelfth Doctor's embarrassment. Bill tells the Twelfth Doctor to come back alive, to which he replies, "Be here when I do."

The First Doctor fetches the Captain another brandy, realising that was why his successor was missing some. He soon leaves to join his older self, while Bill looks after the Captain, but when she grabs the brandy, her hand is revealed to be glass. While outside on Villengard, the two Doctors rest, discussing their respective regenerations. The Twelfth Doctor remarks they have yet to change because they are in a "state of grace", though he himself finds his body starting to deteriorate. He asks why his younger self halted the regenerative process, unable to remember himself. The First Doctor admits he is "afraid" of regenerating and doesn't like to admit that to anyone. The Twelfth Doctor remarks that technically he still hasn't. Before the Twelfth Doctor can answer the question himself, they suddenly come under attack from a creature in a nearby tower, and only stops when the Twelfth Doctor asks the creature to scan him, announcing; "I'm dying!", before going into the tower. He tells his younger self to wait outside to which he begrudgingly agrees.

The First Doctor observes the area, finding the remains of a Dalek casing. He inspects it as Bill sneaks up on him and begins asking why he ran away. The Doctor insists she return to the Captain but Bill insists, asking what he was running to. Interested by the question, the First Doctor responds that he left to discover why good always defeats evil. Bill suggests it might be because of "some bloke" though the First Doctor doubts such. Bill hugs him, thanking him for his efforts. However, when she pulls away, the First Doctor realises she is a glass avatar.

Alone, the Twelfth Doctor meets with the rogue Dalek Rusty, who has taken refuge from the other Daleks hunting it. He remarks on how he is a "good Dalek" though Rusty continues to fire at the Doctor. The Twelfth Doctor decides to come to a truce to which Rusty agrees by disarming his gunstick. Given access to the Dalek Hivemind, the Doctor learns that the pilot and its ship, known as Testimony, were created on New Earth, designed to extract people from their timelines at the moment of their death, and archive their memories into glass avatars. "Bill" is one such avatar, created from her memories. Time suddenly freezes again, the First Doctor and Bill entering the room. Although disappointed at seeing no evil to fight, the Doctors agree to return the Captain to his timeline.

Upon doing so, the Captain asks the Doctors to keep an eye on his family, introducing himself as Archibald Hamish Lethbridge-Stewart, an ancestor of the Doctor's close friend the Brigadier. The First Doctor assures he will do so, the Twelfth Doctor confirming they did. The Testimony remarks the Captain will not remember the incident and a perception filter will ensure the Doctors are not noticed once time restarts. As time resumes, the Doctors watch as soldiers on both sides begin singing "Silent Night" in their respective languages. Soon, each side disarms their weapons and enters the battlefield, leading the Captain and the German soldier to withdraw their weapons and make peace. The Twelfth Doctor explains to the First that he deliberately shifted the Captain's timeline to the start of the Christmas truce, to ensure his life would be spared. The First Doctor is amazed at the fact that his successor altered time to save both men, leading the Twelfth Doctor to describe the truce as a miracle; the only truce of its kind in history. How everyone at war stopped fighting and was kind to each other. He also explains how "generally the universe isn't a fairy tale, but that's where we come in" and that "it never hurts, a couple fewer dead men on a battlefield." This causes the First Doctor to finally understand what being the "Doctor of War" really means.

With the Captain saved, the two Doctors observe the truce for a time and eventually shake hands. As they do, both Doctors' hands start glowing with regeneration energy. The First Doctor declares that he is finally ready, but the Twelfth Doctor states that his predecessor will have to find out what the Twelfth Doctor decides to do "the long way round." The two Doctors bid each other a fond farewell. The First Doctor returns to his TARDIS and sets the controls to return him to the South Pole in 1986. Overcome by his regeneration, the First Doctor declares "here we go, the long way round" and collapses as his TARDIS returns to the South Pole. Shortly afterwards, Ben and Polly find and manage to enter the TARDIS and witness the First Doctor as he is for the last time as he regenerates into his second incarnation right before their eyes.

As the soldiers play football, draw and spend the day together, the Twelfth Doctor watches on, saluting the Captain - who briefly bypasses the perception filter, but dismisses him and returns to his trench. Now alone with Bill's avatar, the Doctor adamantly contends she is not the genuine Bill, only for her avatar to explain that memories are what define a person. To help him understand, the avatar restores the Doctor's memories of Clara Oswald then turns into her. Clara greets the "stupid old man", telling him that it was quite rude of him to forget her in the first place. The Doctor laughs with joy that she's back in his head. Clara reverts back to Bill, who asks the Doctor if he now understands the importance of memory. They are joined by Nardole's avatar who joins Bill in asking the Doctor not to allow himself to die. The Doctor refuses to give the avatars testimony of his life, stating he must be left alone to face his end. They respect his wish and leave after he embraces them both.

The Doctor returns to the TARDIS. He laments how the more he saves the universe, the more it seems to be in need of saving. He briefly argues with the TARDIS, conceding that "they would get it all wrong without me" as he decides to regenerate, saying "One more lifetime won't kill anyone. Well, except me", but not before relaying advice to his next incarnation. He collapses as he does so but manages to return to his feet. Finally ready, the Twelfth Doctor utters his last words "Doctor... I let you go". With that, he takes a last quick gasp for air before he regenerates, the process so violent that the energy ignites the console room as his gaunt face and piercing blue eyes start changing, morphing into a younger-looking and rounder one with hazel eyes.

12 regenerates

The Doctor regenerates.

Smoke fills the console room and the Twelfth Doctor's wedding ring falls from a finger it no longer fits. Once the smoke clears, the Thirteenth Doctor stands in silence for a moment, before grabbing one of the console's monitors. Using its reflective surface, she studies her new appearance in stunned wonderment. Her face cracks into a wide, ecstatic grin as she exclaims "Oh, brilliant!" at the discovery. Excited, she presses a button on the console. Upon doing so, the TARDIS suddenly suffers multiple failures and, hanging thousands of feet above the Earth, sharply jerks causing the doors to face the ground. The Doctor tries to hang on but the doors open, threatening to suck her out. As the Doctor grabs the console, the ship continues to shake, sending all of her books and papers flying out the open doors. The Doctor tries to close the doors, but the time rotor shatters and the panel she's holding onto breaks away, sending her falling out of the ship. In freefall towards the Earth below, the Doctor watches the inside of her TARDIS become swamped by flames before vanishing from sight as she plummets through the clouds...


And Introducing Jodie Whittaker as The Doctor

The Tenth Planet[]


General production staff

Script department

Camera and lighting department

Art department

Costume department

Make-up and prosthetics



General post-production staff

Special and visual effects


Not every person who worked on this adventure was credited. The absence of a credit for a position doesn't necessarily mean the job wasn't required. The information above is based solely on observations of the actual end credits of the episodes as broadcast, and does not relay information from IMDB or other sources.

The Tenth Planet was written by Kit Pedler and Gerry Davis

Uncredited crew[]





Food and beverages[]





  • The First Doctor asks the Twelfth Doctor, not realising he's talking to his future self, if he is another Time Lord.
  • The Twelfth Doctor says the First Doctor was "weak as a kitten" when he started regenerating.
  • A bird freezes mid-air.
  • Glass avatars, part of the Testimony, are creatures with the ability to freeze time and extract memories and personality of a dying person so they will remain forever.
  • The TARDIS team encounters Dalek mutants which have mutated even further. The Captain first thinks they are rats, saying he is used to those.



The Doctor[]

  • Due to the timelines being out-of-sync, the Second Doctor will forget about trying not to regenerate and so the Twelfth Doctor does not remember it.
  • The First Doctor's face is, according to the Twelfth Doctor, "all over the place" as a result of him trying to hold off his regeneration. This also results in him regaining the strength he had lost during his fight with the Cybermen on Snowcap.
  • The First Doctor doesn't know who his future self is, and keeps denying it even after the Twelfth Doctor reveals himself to him. Only after the Testimony shows him snippets of his future does he finally give in and accept it.
  • The First Doctor first thinks the Twelfth Doctor is another Time Lord trying to capture him for running away with a TARDIS.
  • The First Doctor later attempts to make the Captain understand better, saying that the Twelfth Doctor is his nurse, however improbable due to him being a man.
  • The Twelfth Doctor calls the First Doctor Mister Pastry, Mary Berry, and Corporal Jones.
  • The Doctor is called "The Destroyer of Worlds", "The Imp of the Pandorica", "The Oncoming Storm", "The Shadow of the Valeyard", "The Beast of Trenzalore", "The Butcher of Skull Moon", "The Last Tree of Garsennon", "The Destroyer of Skaro" and "the Doctor of War".
  • The Twelfth Doctor attempts to distract the First Doctor with the blinking lights on his astral map after his unfavourable remark to Bill about the Twelfth Doctor needing her for cleaning his TARDIS.
  • The double-breasted blazer of plum purple velvet that the Third Doctor wore on his trip to Spiridon is hanging in the Twelfth Doctor's TARDIS.
  • The Twelfth Doctor's ring falls off the Thirteenth Doctor's hand, as it doesn't fit on her finger.


  • The First Doctor calls the TARDIS "the Ship", much to the Twelfth Doctor's nostalgic joy.
  • The First Doctor disapproves of the Twelfth Doctor's TARDIS, saying about the console room that it is "the flight deck of the most powerful space-time machine in the known universe, [it's] not a restaurant for the French".
  • The Twelfth Doctor still has blackboards in his TARDIS.
  • Bill remarks the windows on the First Doctor's TARDIS exterior are the wrong size.
  • The First Doctor's TARDIS has a name tag on the console that says Bernard Wilkie.
  • The Cloister Bell rings in the Twelfth Doctor's TARDIS before he regenerates.
  • The Twelfth Doctor's TARDIS interior ends up exploding due to "Multiple Operations Failures" after the Thirteenth Doctor causes a "Systems Crisis" by clicking a red button on the console. The exploding TARDIS throws the Doctor out as it dematerialises.


  • The British soldiers sing "Silent Night" and the German soldiers sing the German version, known as "Stille Nacht".

Story notes[]

  • The Thirteenth Doctor's scene was written by the incoming showrunner Chris Chibnall, as had been the case when Steven Moffat wrote the Eleventh Doctor's first scene in The End of Time when he took over from Russell T Davies.[1] Chibnall's wrote the scene in a manner which made no reference to the new Doctor's sex, but Moffat had come to suspect that the Doctor would be female.
  • The cinematic, DVD and Blu-ray releases featured two documentaries: The End of an Era, a retrospective and behind-the-scenes look, before the showing, and Twice Upon a Time at the end, an in-depth look into the making of the Christmas special.
  • The special features a "Previously on Doctor Who..." sequence saying "709 Episodes ago" and showing footage from The Tenth Planet with William Hartnell, Anneke Wills and Michael Craze as the First Doctor, Polly Wright and Ben Jackson respectively. This scene makes use of two aspect ratios. The footage reframes from 4:3 black-and-white to 16:9 colour, slowly morphing Hartnell into David Bradley, and Lily Travers and Jared Garfield then appear as Polly and Ben, re-enacting missing segments on Snowcap from said episode. Following the First Doctor's return to his TARDIS, the episode briefly goes back to 4:3 black-and-white after Bradley's Doctor is seen lying on the floor unconscious, cutting to the original regeneration from Hartnell into Troughton, and visually bookending the First Doctor's involvement in the narrative.
  • This story features a rare instance in which actors that only appeared through use of archive footage were also credited. Another notable instance of this happening is The Day of the Doctor. William Hartnell's credit has been changed from "Dr. Who" to "The Doctor."
  • Rachel Talalay had actually shot a number of scenes from The Tenth Planet, with a complete set reconstruction, recast characters, and the series 10 Mondasian Cybermen. She said in an interview that she tried to make both the set, and the cinematography, as accurate to the original scenes, and original production values, as much as possible. She did admit to having fun with some parts of the set in particular, and embellishing with a "60s feel", and noted that some details of the action had to be invented. These scene recreations were not used in the final edit of Twice Upon a Time; the original footage was used in its place. However, these specially shot re-tellings were shown in the cinema feature Twice Upon a Time.[3]
  • The First and Twelfth Doctors meeting also features the scene acted out differently in The Doctor Falls and Twice Upon a Time, similar to how episodes in the 60s reshooting the prior scene's cliffhanger, often resulting in little differences. The same situation also occurred when The Runaway Bride followed the Doomsday cliffhanger 11 years prior.
  • The recreated Hartnell TARDIS interior set actually included props from the original set in the 1960s. As told by Mark Gatiss, these included the brass pillars, which are indeed the brass pillars from way back in 1963. Other aspects of the set were recreated.[3]
  • The Twelfth Doctor's regeneration has a new visual effect, and even sound effect, to those used previously in the BBC Wales series. Resembling slow travelling, elongated golden lightning. It is the first regeneration for the Doctor, since the Seventh Doctor's in 1996, to use an effect which is visually distinct from that seen in The Parting of the Ways, with the Ninth Doctor up to The Doctor Falls.
  • Toby Whithouse, with his performance here as the German soldier, is the fifth person to have both written for and acted in Doctor Who. The others being Victor Pemberton, Derrick Sherwin, Glyn Jones and Mark Gatiss. Though Whithouse and Gatiss are the only two who have written and acted in the revived series and are the only two to have written multiple stories. Gatiss and Whithouse were the most prolific writers during Steven Moffat's time as showrunner after Moffat himself.
  • Mark Hedges, 1st assistant director, last worked on a DWU programme on Invasion of the Bane, the very first episode of The Sarah Jane Adventures in 2007. Gareth Meirion Thomas, sound recordist, last worked on Torchwood: Miracle Day in 2011. This was the first, and so far only, Doctor Who credit for both crew members.
  • This is the third consecutive regeneration story to include the word "time" in the title, following The End of Time and The Time of the Doctor.
  • Nikki Amuka-Bird is credited as "Helen Clay" on-screen, and as "The Glass Woman" in Radio Times.
  • When Bill's glass avatar and the Doctor talk and she restores his memories of Clara Oswald, the music from The Husbands of River Song when the Doctor and River were on a date before the Singing Towers of Darillium plays.
  • On the last day of filming, Mark Gatiss brought in the jacket that Jon Pertwee wore in Planet of the Daleks. It was featured hanging from a stand in the background in the Twelfth Doctor's TARDIS during the regeneration scene.[4] He also published a Behind the scenes picture of Capaldi wearing the jacket.[5] Seizing the opportunity, Rachel Talalay decided to place it in the background during the regeneration.
  • Nardole having invisible hair was already jokingly stated by Steven Moffat in a BBC post-episode interview. There he also stated that Nardole was the only one able to see it through his glasses and that it was purple.[6] Matt Lucas had been aware of the invisible hair, but not the glass nipples.[3]
  • The Twelfth Doctor's final lines about his name and how humans would understand it are directly taken from a theory Peter Capaldi stated at a press screening interview of The Pilot.[4]
  • The Twelfth Doctor's line "never, ever eat pears" is a tweaked version of the one in a hidden scene in Human Nature by the Tenth Doctor. It was also said in Hell Bent by the Twelfth Doctor.
  • This is the first regeneration story in the revived series without any direct connections to the Last Great Time War.
  • Clara's avatar originally appeared alongside those of Bill and Nardole, with the Doctor's group hug taking them all in. Moreover, rather than the "empty battlefield" speech serving as the Doctor bidding the avatars adieu, he instead would have teased them by saying that one of them was his favorite companion but not saying who, to the ladies' confusion (while Nardole assumes it's him), which would have given his return to the TARDIS a much lighter tone. However, Jenna Coleman wasn't able to appear onset due to her commitment to the second season of Victoria, so Steven Moffat re-wrote it so she could appear via green screen. She filmed her cameo seperately on a sound stage normally used by Top Gear. [7] Moffat said, "How many times have I killed that girl off and she was right there in my last shot! It's absolutely extraordinary. The unkillable Coleman!"
  • For the First Doctor's TARDIS, the wall with photographs of roundels was replaced with the wall behind the Curator from The Day of the Doctor.[8]
  • When the Doctor's ring falls off her finger, only the secondary band of the ring was in the shot. This was because the first band of the ring was Peter Capaldi's wedding ring.
  • This is the first multi-Doctor story to explicitly take place during a previously broadcast TV story from the earlier Doctor's perspective, though footage from the unbroadcast serial Shada was used in The Five Doctors.
  • This was the last episode contributed to by production designer Michael Pickwoad before the announcement of his death in August 2018.
  • This episode was originally not going to be made. The Twelfth Doctor's regeneration was meant to finish in The Doctor Falls, but Chris Chibnall didn't want to start his run with a Christmas special. Worried that the series might lose its Christmas slot, Steven Moffat convinced Peter Capaldi to do the Christmas special.[9] Despite so, Chibnall did not use the Christmas slot the subsequent year, opting for a new-years special instead.[10]
  • Steven Moffat planned to explain why the First Doctor's clothes changed to fit the Second Doctor upon regeneration, but decided against it.[11]
  • While at the New York Comic Con, Steven Moffat discussed the idea of the Twelfth Doctor meeting his original self, as he thought it would be interesting for that version of the Doctor to see what he had become after so many lives. When he had observed that this notion was sadly impossible to realise due to the fact that William Hartnell had died in 1975, Peter Capaldi jokingly suggested that David Bradley play the role, as he played Hartnell in An Adventure in Space and Time.
  • Steven Moffat originally planned to re-visit the First Doctor early in his run. Seeing as the Mondasian Cybermen appeared in World Enough and Time/The Doctor Falls, he decided to re-visit The Tenth Planet.
  • Although the First Doctor had softened considerably during his tenure, Steven Moffat nonetheless wanted to reflect the received wisdom that he was a crotchety, irascible old man. This would also provide an opportunity to poke fun at some of the more antiquated elements of his era, such as the condescending and chauvinistic attitudes that it sometimes adopted towards female characters, even though the Doctor himself had rarely exhibited these traits.
  • Rachel Talalay, who made her home in Canada, was initially uncertain about a protracted stay in the United Kingdom, especially since she was in need of surgery to remove her ailing gall bladder. However, she ultimately found herself unable to refuse the assignment.
  • Given the weighty subject matter in which not one but two Doctors would be contemplating the end of their lives, Steven Moffat sought as many opportunities for levity as possible.
  • Steven Moffat decided that there would be no actual villain; instead, the plot would hinge on a mistake by the far-future Testimony Foundation, which was inspired by Moffat's view that memories were a person's essential building blocks.
  • Pearl Mackie was surprised and delighted to receive a message from Steven Moffat asking if she was available to return, since she had assumed that her time on the programme had ended with the completion of season ten.
  • Steven Moffat wrote the role of the Captain especially for Mark Gatiss, as he wanted his friend to take part in his final episode.
  • Steven Moffat had considered featuring the 1914 Yuletide on previous occasions, but he had demurred as he searched for a way to do so in a respectful manner.
  • Originally, the Twelfth Doctor revealed that Ben and Polly had gotten married after leaving the TARDIS, and were now running a pub in Weston-super-Mare. This may have been a nod to the fact that Michael Craze later ran a pub. It would have contradicted Death of the Doctor, where Sarah Jane Smith revealed that they ran an orphanage in India.
  • Chris Chibnall asked Steven Moffat to incorporate the destruction of the TARDIS console room into the script, since he was planning to introduce a new standing set.
  • After receiving the script, David Bradley decided to avoid the sort of outright impression of Hartnell that he had attempted for An Adventure in Space and Time.
  • The first material to be filmed was the scenes in the Antarctic, since the set would also be needed for throw-forward material in World Enough and Time/The Doctor Falls, which was to be broadcast in twelve days.
  • The First Doctor's TARDIS and costume were both new for the special, although David Bradley asked to wear the Karakul hat he had sported in An Adventure in Space and Time.
  • As with the old-style TARDIS seen in Hell Bent, the First Doctor's console room was represented by a modified version of the set constructed for An Adventure in Space and Time, which was transported to Roath Lock from its regular home at the Doctor Who Experience, which was scheduled to close a few weeks later. The set's use for Hell Bent had been marred by a measurement gaffe, which resulted in the manufacture of an undersized outer door; this error was now corrected.
  • A replica of the Astral map originally seen in The Web Planet was built.
  • The recreation of the Christmas armistice proved to be an emotional experience for the cast and crew, especially during the singing of "Silent Night".
  • The cuddle between the Doctor, Bill and Nardole was ad-libbed, and referenced a similar group hug in Oxygen.
  • Rusty was represented by the same casing used for his original appearance in Into the Dalek. It had been on display at the Doctor Who Experience during the intervening years, and received only minor modifications for its inclusion.
  • In the ruins of Villengard, the Doctors originally faced landmines and tentacled creatures before they reached the tower. In the process, the First Doctor used the Twelfth Doctor's sonic screwdriver to rescue his future self from the monsters. The Twelfth Doctor then remembered that this was the first time he had ever used a sonic screwdriver.
  • The opening caption initially referred to Episode Four of The Tenth Planet as being 705 episodes ago, rather than 709, but Tom Spilsbury caught the error shortly before the story's broadcast on Christmas Day.
  • The special had a cinema release in Brazil, Australia, Denmark, Canada and the United States.
  • Bill didn't appear in early drafts. Steven Moffat included her to add more fun to the story.[12]
  • In a 2024 interview to promote Boom, Steven Moffat admitted that he "didn't love" the special, finding it just "okay". "I think it’s soft in the middle. The ending is good".[13]
  • In an interview following the episode's broadcast, Mark Gatiss said he cried at the thought of playing the Brigadier's grandfather when he finished reading the script. However, the Haisman Literary Estate asserted their control of the backstory of the Brigadier, stating that Archibald was actually the Brigadier's great-uncle who appeared in Night of the Intelligence. They later compromised in What's Past is Prologue by implying that Archibald may secretly be the biological father of the Brigadier's father, thereby allowing for either interpretation.


  • 5.70 million (UK overnight)[14]
  • 7.92 million (UK final) [15]
  • 1.15 million (BBC America overnight)[16]
  • 2.2 million (BBC America final)[17]

Filming locations[]

  • Dragon Studios in Llanilid.

Production errors[]

If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.
  • Bill's shirt changes constantly throughout the entire episode, from the rainbow shirt that was seen in Smile, to a new shirt which we have not seen before.
    • However, this could be attributed to the fact that this version of Bill is a collection of her memories and not her physical self.
  • Nikki Amuka-Bird fluffs a line: “Step out of the caps-ul.” She should have said “Cap-sule.”
  • When examining the glass woman, the Twelfth Doctor’s right hand is in line with his waist. Next shot and his hand is down his side. In the next shot, his left hand is next to his waist.
  • When the Captain is taken from the World War One battlefield he has his revolver in his hand. After he falls to the ground at the South Pole, the gun is in his holster and he has to draw it again.
  • A few times throughout the episode, the doors of the first Doctor's TARDIS open as he approaches them even though he didn't operate the door control on the console.
  • After the Captain requests a favour from the Doctors, the First Doctor can be heard saying "Oh, anything. Name it," but his mouth is not actually moving after the word "oh."
  • In the Christmas scene on the battlefield, fire is seen in several places. In the shots where objects are in front of the fire, the smoke is seen to rise in front of the object, despite the fire being behind.
  • When the medics run with the stretcher, it is brown and has a large stain on it. But when the soldier is on it, it changes to black.
  • During the scene in which the soldiers are playing football, the shot is flipped. This is visible due to the soldier's uniforms.
  • Before stepping in to the TARDIS to regenerate, the Doctor is seen wearing black and blue running shoes. In the next shot where he's in the TARDIS, he is wearing his usual black boots.
  • In the original episode of The Tenth Planet, the First Doctor regenerates with Ben and Polly at his side. In this episode, he regenerates alone.
  • The Twelfth Doctor begins regeneration with his back to the stairs, but immediately following regeneration, the Thirteenth Doctor is standing at a different angle and is further away from the stairs.
  • When the Doctor catches herself from falling through the TARDIS doors with her foot, her boot briefly changes to a different shoe.
  • In the shot where the Doctor falls through the TARDIS doors, the bottom-right section of wall has clearly been digitally extended on the last frame.


  • The Twelfth Doctor would be killed. The Twelfth Doctor was killed in the previous story, he just refused to regenerate then.
  • Because the opening was set in the events of The Tenth Planet, Cybermen would appear. Although this was technically true, they only appeared through the use of archival footage from said story.
    • A full recreation of several scenes were originally filmed for this purpose.
  • Carole Ann Ford would return as Susan Foreman. This was proven false.
  • The Captain would turn out to be Gilbert MacKenzie-Trench, the man who created the iconic police box design. The Captain was revealed to be Archibald Hamish Lethbridge-Stewart, an ancestor of the Brigadier.
  • The Doctor would regenerate while falling. The Doctor fell out of the TARDIS after regenerating instead.
  • According to the Daily Mirror, this story would see the last day of the Time War from the perspective of the First Doctor and the Twelfth Doctor. This was proven false.
  • Matt Smith would return as the Eleventh Doctor. This was proven false, although archive footage was used of all of the Doctor's incarnations up to the Twelfth by the Testimony to prove to the First Doctor that the Twelfth Doctor was indeed his future incarnation.
  • The videotape prop of "The Daleks' Master Plan 1-12" was a real domestic videotape recording of all twelve episodes loaned to the crew by a film collector. While it is possible missing episodes could exist on off-air videotape cassette recordings, this simply isn't the case. It is highly unlikely a private collector would loan such a rare item without realising the BBC would most likely return it to their archives and make it publicly available. Furthermore, a domestic tape of 1965/66 quality could not contain more than roughly 120-160 minutes, while all twelve episodes are a total of 300 minutes.


Home video releases[]

DVD releases[]

A stand-alone DVD was released in region 1 on 13th February, 2018, in region 2 on January 22nd, 2018 and in region 4 on February 7th, 2018.

Blu-ray releases[]

A stand-alone Blu-ray was released on the same dates in all markets as the DVD. The Blu-ray has special features including a recording of the Doctor Who panel at San Diego Comic-Con 2017.

4K Ultra HD Blu-ray releases[]

This story was released on Ultra HD Blu-ray in the UK on September 24th, 2018, in Australia on September 25th, 2018 and in North America on October 17th, 2018. It is the first Doctor Who story to be released on the format. The story was not shot in 4K and so was upscaled, however this release makes use of HDR colour depth not available on the DVD and Blu-ray releases. It contains the same special features as the standard Blu-ray release, which is also included as a separate second disc.

The US release came on October 2nd, 2018. It is notable for using the 2018 version of the logo on the cover art rather than the version used during Capaldi's tenure as the Doctor. The disc contents are identical to the UK release (including an FBI warning, included on the UK pressing of the disc).

Digital releases[]

  • In the United Kingdom, this story is available on BBC iPlayer as part of Series 10.

External links[]