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Recap / Doctor Who S36 E11 "World Enough and Time"

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World Enough and Time
Written by Steven Moffat
Directed by Rachel Talalay
Air date: 24 June 2017
Part 1 of 2

Jorj: Who are you?
Missy: Well, I'm that mysterious adventurer in time and space, known only as Doctor Who, and these are my disposables — Exposition and Comic Relief.
Nardole: We're not functions.
Missy: Darling, those were genders.

The one where the genesis of the Cybermen and the undoing of a companion are revealed.

And, funnily enough, it's the one where the show finally goes and does a multi-Master story...

This is the first half of the two-part Series 10 Season Finale of Doctor Who. Its denouement also continues into the 2017 Christmas Episode to form, in total, a three-part Grand Finale for Peter Capaldi's tenure as the Twelfth Doctor.

This is the story of how the Twelfth Doctor died...

The Doctor and Missy (the Master)'s relationship has evolved since he chose not to execute her. After decades of imprisonment in the Vault under his watchful eye as he kept to his 1,000-year vow, she seems to be on the verge of a Heel–Face Turn. Few things would please these two Time Lords more than to be friends again, as they were before madness of others' making sent her down an evil path. But the Doctor knows that he must be careful — Hope Is Scary, and seductive.

To Bill and Nardole's anxiety, the Doctor decides he will test Missy's sincerity and capacity for good, inspired by a long-ago promise they made to each other to see the universe together. He brings the TARDIS to a gigantic spaceship in need of aid: It is caught in the gravitational pull of a black hole. But Missy will be filling his role — down to his name — while he hangs back in the TARDIS to observe her actions and interactions with both Bill and Nardole and the crew of the ship, coaching the trio by earpiece as required. After all, the universe shows its true face when it asks for help, and those who are asked show their true faces in how they respond.

As you can probably guess, lots of trouble occurs. The true Doctor joins the fray, but too late to save Bill from being shot — through and through — by an anxious alien technician. From there, her body ends up transported to the other end of the ship, which is 400 miles away and unreachable via TARDIS because the ship, ever since it became trapped in the black hole, has been suffering Time Dilation caused by gravitational pull. Luckily, she is in a hospital and soon up and about again! Unluckily, time is flowing much, much faster at Bill's end than at the Doctor's: ten minutes for him, Missy, and Nardole is 2.84 years for her. Moreover, this hospital is ministering not-so-tenderly to the humans of the planet Mondas — Earth's long-lost twin. This Dying Race of humans is "evolving" to survive the physical effects of dilation via artificial limbs and organs. And since her heart was vaporized, Bill has already been forced to take the first steps toward a full "upgrade".

When, not if, the Doctor, Missy, and Nardole reach Bill by travelling through the ship itself — the Doctor will not let his beloved companion pay the price for his decision to test Missy if he can help it — they will also find both the first generation of Cybermen and another version of the Master waiting for them. It's Missy's previous self. You know, the one who can't decide whether you should live or die.

And with this, the story continues in "The Doctor Falls"...


  • AcCENT upon the Wrong SylLABle: In keeping with the Mondasian Cybermen's first appearance, the Cyber-converted Bill speaks like this:
    I-iii WAITed forrrrr yoUUUUuuuuu.
  • Anachronic Order:
    • A Moffat favourite, this pops up in this episode seemingly showing the Doctor regenerating, then in the adventure itself, and then flashing back to the Doctor trying to convince Bill and Nardole to come with Missy.
    • Then there's the whole angle of the previous incarnation of the Master finally turning up for the party, hopefully to resolve the burning question of how we went from him to Missy.
  • And I Must Scream: The nurse appears to treat the patient who's calling out in pain by adjusting his dosage. Bill discovers that she only turned down his volume control and he's still crying out in agony.
  • Apologetic Attacker: As Jorj aims a gun at Bill, he says "I'm sorry, but you're the reason they're coming." Why? She's the one human in the group.
  • Artistic Licence – Biology: The thousands of people living on the lower decks are supposedly descended from an original population of just 20 individuals (from a race who are supposed to be more-or-less genetically identical to Earth humans). While not quite an Adam and Eve Plot, this still doesn't represent anything like a big enough gene pool to produce a healthy population; after a thousand years, they should have inbred themselves into near-extinction.
  • The Atoner: Missy seems ready to become this, and the Doctor sets her on a Redemption Quest with his Swapped Roles gambit to test her. Then her other self, who is leagues away from her present Character Development, shows up and is prepared to convince her not to cross that bridge.
  • Background Halo: In an inversion(?), the nurse's hat gives her background horns.
  • Backstory: The Mondasian Cybermen's tragic backstory is depicted and explored at length in this episode. Or at least one branch of them.
  • Bait-and-Switch Compassion: Bill finds a patient at the hospital who is unable to speak, but has been given a mechanical voice box which they use to constantly emote the word "pain". A nurse approaches the patient and offers to help them, and is seen adjusting some of the machines the patient is connected to. When Bill gets a closer look at the patient, she realises that all the nurse did was set the voice box to mute.
  • Bait-and-Switch Comment: Mr Razor does this all the time.
    Razor: You are dear to me. You are my dearest person. You are like...
    Bill: I know.
    Razor: A mother to me.
    Bill: [Beat] Definitely not a mother.
  • Battleaxe Nurse: The formidable nurse in the hospital where Bill ends up. When patients complain about pain, she just turns their volume off.
  • Beard of Evil: The Saxon Master now has a Delgado/Ainley-era goatee.
  • Being Good Sucks: Missy is genuinely trying to be good as the Doctor tests her, and later as she aids the Doctor and Nardole in rescuing Bill. Unfortunately, her previous self turns out to have been behind Bill's terrible fate specifically because she wants to be good, and he taunts her that the Doctor will not forgive either of them for this foul deed. Rather than stand up to her previous self, hope that the Doctor will understand the situation, accept any consequences he might lay down, and use this tragic development as another thing she Must Make Amends for via Redemption Quest, she seems ready to give up on goodness altogether as of the Cliffhanger.
  • Best Served Cold: The Saxon Master was willing to spend ten years befriending Bill just to stymie the Doctor's plans to reconcile with his future self.
  • Big Bad: The Harold Saxon incarnation of the Master. Surprisingly, Missy is not in on his plot — she doesn't remember her time in this ship as Saxon at all — and seems to have potential for a Heel–Face Turn until he reveals what he's done to the companion of the Doctor who has been trying to redeem her. Indeed, part of the point of his Evil Plan is to make sure she never makes one.
  • Big "NO!": The episodes starts off (in Anachronic Order) with the Doctor seemingly about to regenerate on a desolate ice planet shouting this.
  • Bitch in Sheep's Clothing: In the creepy hospital, Bill makes friends with "Mr. Razor", a strange, dishevelled man who works as a janitor. And then he leads her right to the conversion theatre. And then he turns out to be the Master.
  • Bloodless Carnage: Bill gets a huge hole blown in her chest, yet no blood or organs are shown, probably because it was an energy weapon that cauterized it. Mr. Razor later comments her heart was "broken".
  • Body Horror: Being a Cyberman. They're created in a pure Medical Horror setting, and every last one is in constant agony. The machinery doesn't stop the pain so much as program you to not care.
  • Book Ends:
    • Twelve's first series finale, "Dark Water", also involved a shady institution secretly harvesting people to become Cybermen, and ended with a seemingly-minor character working for this institution revealing themselves as an incarnation of the Master while a companion/major recurring character reveals they've been forcibly cyberized.
    • Steven Moffat is leaving the series on an epic multi-part story that concludes in the holiday season featuring John Simm's incarnation of the Master and the Doctor reluctant to regenerate, nearly identical to circumstances in which Russell T Davies had passed the torch on to him.
  • Break the Cutie: Putting her trust in the Doctor and going along with his risky plan to redeem Missy, sweet, plucky Bill Potts is shot through the chest and ends up alone and trapped in a hospital where she's saved, yes, but then first Conditioned to Accept Horror and later forced to undergo Unwilling Roboticization. This is because, where minutes are passing for the Doctor as he tries to rescue her, years are passing for her as she waits... and waits. To make matters even more heartbreaking, the one friend she has for all these years has just been waiting to betray her all along, waiting until the last possible moment to do so. While she is a Cyberman, she is still capable of feeling emotions along with pain, the last shot of the episode being a tear emerging from her eye.
  • Brits Love Tea: Mr. Razor and Bill "enjoy" this regularly. As far as he's concerned it's the real horror of the hospital. And this is the "good" tea.
  • Brutal Honesty: When Bill asks the Doctor to promise her he won't let her get killed if she agrees to help him test Missy, he replies "I can't promise you that." He does say he will protect her ("Within reason.").
  • The Bus Came Back: The Harold Saxon incarnation of the Master finally returns, making this storyline both his first appearance since the Tenth Doctor's Grand Finale "The End of Time" and the first multi-Master story in the televised continuity. And, of course, the very first breed of Cybermen from "The Tenth Planet" appear for the first time since them. In fact, Bill becomes the very first of them.
  • Call-Back:
    • In "Extremis", the about-to-be-executed Missy begged for her life, saying she could change, asking the Doctor to teach her to be good. She has since spent decades in the Vault, forced to go "cold turkey" from doing evil, as revealed in "The Lie of the Land". In that episode's ending and the two that followed, she showed the potential for a Heel–Face Turn, and now he will test her sincerity.
    • The Doctor promised Bill he would be able to save her in "Oxygen" and he did (twice), and her hope that he had a plan to defeat the Monks all along helped sustain her for six lonely months in "The Lie of the Land". Now she is trapped in a hospital and faces being converted into a Cyberman, as years pass for her thanks to Time Dilation as she waits for the Doctor to arrive. He turns out to be too late this time.
    • The Master disguises himself with a Latex Perfection mask, something the Roger Delgado and Anthony Ainley incarnations frequently did.
    • The Master has to disguise himself so Bill won't recognise the former Prime Minister of Britain, Harold Saxon. Although to be fair, when "Harold Saxon" was the Prime Minister, Bill was probably about 10 years old at most, and likely paid very little real attention to national politics.
  • Character Focus: After the opening ten minutes or so, this episode focuses on Bill's side of the story as she endures The Slow Path in the hospital waiting for the Doctor, Missy, and Nardole.
  • Cliffhanger: The Harold Saxon Master has had a hand in the creation of the original generation of Cybermen, poor Bill has been completely Cyber-converted, Missy appears to have given up her Heel–Face Turn upon learning that her earlier self has done this to Bill, the Doctor's TARDIS is on the other end of the ship and only accessible via the lifts, and the story will end when The Hero Dies.
  • Comically Missing the Point: Missy playing The Hero.
    Missy: Well, I am that mysterious adventurer in all of time and space, known only as Doctor Who. And these are my disposables, Exposition and Comic Relief.
  • Conditioned to Accept Horror:
    • Bill becomes this with regards to the hospital. She is initially horrified by what goes on around her, but since she's stuck there, she has no choice but to learn and understand why things are the way they are. Once she does, she accepts them as just a sad reality and even becomes a janitor alongside Mr. Razor.
    • For that matter, none of the Mondasians in the city seem to care about what is being done to their fellow citizens in the hospital; no La Résistance is forming. This is because the breakthroughs going on in the hospital are what will make it possible for everyone to leave this miserable, polluted world for greener pastures on the other floors, which are (supposedly) teeming with enemies they will have to battle.
  • Continuity Nod:
    • For the third time in series history, just as a Doctor's tenure is about to end, he encounters the Mondasian Cybermen.
    • It's the second time a Doctor has fought the Harold Saxon incarnation of The Master as their tenure came to an end.
    • The episode begins in an Arctic-like environment, where The Doctor begins regenerating, not the first time this has happened both in the Arctic and in an episode with Mondasian Cybermen. It later turns out that it is in fact the same place and time as the original example, to within a few minutes at most.
    • Saxon-Master is armed with his laser screwdriver, as in the Series 3 finale three-parter. In addition, once again he decides to align himself with a dying race of people who are desperate to survive, even if it means becoming inhuman...
    • The intruder alert alarm on the spaceship is a four-beat rhythm that Missy rather likes... (also Foreshadowing).
    • Once again, the Twelfth Doctor has to deal with Missy and the Cybermen in a Season Finale two-parter. And Bill undergoes piece-by-piece Cyber-conversion, a slower take on the fate of Danny Pink.
    • The Twelfth Doctor once again finds himself helpless to save a beloved companion from suffering a terrible fate — death in Clara's case, near-death and Cyber-conversion in Bill's — and seems to blame himself for the tragedy. In Clara's case, it's because he didn't rein in her more reckless impulses; in Bill's case, he convinced her to help him test Missy, knowing that she trusted him to keep her safe.
    • Jorj, the technician on the spaceship, appears to be of the same blue-skinned species as Dahn-Ren from "Oxygen", which also involved the TARDIS crew responding to a distress call with devastating personal consequences.
    • In "The Eaters of Light", the episode immediately preceding this one, a major plot point was that the portal to the Eaters' dimension was subject to Year Inside, Hour Outside. In this story, Time Dilation is central to the plot — 2 days pass at the front of the ship, 1,000 years in the back.
    • Missy at one point calls the Doctor an idiot, and he replies with "Always." note 
    • Missy derides the idea that the Doctor's companions are his real friends, as she did with Clara Oswald.
    • Bill's Cyber-conversion is not unlike Peri Brown having another consciousness overwriting hers in "Mindwarp". Notably, while Peri was originally Killed Off for Real in that story, her fate was given a Retcon at the eleventh hour as it came off as far too brutal.
    • The Twelfth Doctor is trying to rescue Bill, but it's complicated by the fact that Time Dilation affects the ship they're on opposite ends of, so long before he gets there she is Cyber-converted. This is similar to the crisis at the heart of "The Girl Who Waited", in which Amy Pond was trapped in an accelerated time stream intended for terminally ill people and aged decades into an old, bitter woman while only minutes passed for Rory and the Eleventh Doctor, leaving them to puzzle out a way to save her younger self.
    • With Missy playing at being the Doctor, the issue of the latter's real/original name is brought up again, albeit Played for Laughs. They were childhood friends, after all. If anyone knows what it is then it would be her.
    • Oswin Oswald would surely sympathize with Bill Potts's plight, too — trapped and helpless in a hospital in deep space, Unwilling Roboticization threatened.
    • The Twelfth Doctor wanting Missy to see the true beauty of the universe, believing it will induce a Heel–Face Turn in her, recalls his gambit to remind Rusty of what it was that made his radiation-damaged mind turn against the Daleks in "Into the Dalek".
    • Missy takes on the Doctor's role and name in the early going, much the same way Clara Oswald did in "Flatline" and "Death in Heaven" — the latter of which also featured Missy and the Cybermen. As in "Flatline", he is able to coach his "student" from afar (via an earpiece this time).
    • Heather made The Promise back in "The Pilot" not to leave without Bill and then she became possessed by living spaceship fuel and tried to hold herself to it in the worst way. The Doctor convinced Bill not to accept her offer to see the universe as a passenger and to free Heather from the promise. But now, the Doctor effectively wants Missy to become his passenger, remembering his old pact with her that was never fulfilled. Also counts as Book Ends for Series 10.
    • The Doctor and Bill Potts previously encountered human colonists of the future in "Smile".
    • The determination of the Mondasians to survive by any means necessary, even if it means innocent lives are sacrificed in the process and the survivors end up with horribly altered bodies, is akin to the Landlord's desperation to keep his mother alive via the Dryads in "Knock Knock".
    • Moffat actually went out of his way to avoid contradicting Marc Platt's "Spare Parts", one of the most well-regarded and beloved Big Finish episodes ever. The Mondasian Cybermen's Backstory here is a variation on the one presented for them in "Spare Parts" (with added Time Dilation) and includes homages to both the pseudo-1950s setting of Marc Platt's story and the scene with the partially converted Yvonne Hartley, but doesn't retcon that story's direct link to "The Tenth Planet", instead featuring a colony ship of Mondasians who presumably fled the planet Mondas long before "Spare Parts" happened.
    • The Doctor subdues Jorj by breaking out the Venusian Aikido, for the first time in a very long while. The Third Doctor (whom the Twelfth Doctor quite resembles, especially in his first outfit) was a proficient user of the martial art.
    • The Master adopting an alias, this time as "Mr. Razor". He's also gone back to his long-lost habit of assuming elaborate disguises, last seen in the classic series, and is back to sporting an evil goatee while male, as he's done in every male incarnation while in the prime of life — the exceptions being his degenerated form and his engineered personality as Professor Yana, who forgot he was the Master.
    • Mr. Razor tells Bill his line about the patients not feeling pain was "A clever lie", much like the Eleventh Doctor said in "Let's Kill Hitler".
    • The Master having revealed himself, he says he doesn't think of the Cyber-conversion as "Project Exodus", but instead as a "Genesis", specifically, the "Genesis of the Cybermen". This references the title of the Fourth Doctor story, "Genesis of the Daleks".
    • Due to Timey-Wimey Ball, this is both the first and second times that a version of The Master has created a version of Cybermen. The first, from audience perspective being the "Dark Water"/"Death in Heaven" two-parter, while this is the first chronologically, as these are the original Cybermen.
    • We've seen the Doctor return to but ultimately prove unable to stop the genesis of a very old foe before, twice ("Genesis of the Daleks" for the Daleks, "The Snowmen" for the Great Intelligence).
    • Missy not being able to remember her past self's role in events is a nod to how when previous Doctors interact the older regenerations lose their memory of events, lest it cause too much of a paradox.
    • Bill's single tear at the end of the episode echoes Yvonne Hartman doing the same.
    • Long after "The Lie of the Land," Bill finds herself living in another gloomy dystopia.
    • When Bill protests helping Missy because she's a murderer, the Doctor points out that Bill herself is eating a bacon sandwich, almost scornfully telling her "Go tell a pig about your moral high ground." The Sixth Doctor had decided to become a vegetarian in "The Two Doctors" and going by Twelve suggesting Bill eat a vegan wrap in "The Pilot", apparently he's back on itnote .
    • The Doctor recognises the converted Bill specifically as a Mondasian Cybermen on sight. Several expanded universe sources had identified the original variant from "The Tenth Planet" as CyberMondasian (or CyberMondan) to distinguish them from later Cyberman models.
  • Conversation Cut: It takes a while to convince Bill to go along with the Doctor's plan, so their conversation cuts to different parts of the university (as well as being a How We Got Here flashback).
  • Costume Evolution: The designs of the proto-Cybermen in the hospital slowly change over the ten years Bill spends in there. The first ones look like patients in surgical gowns with their faces covered by bags, reliant on IV drips they have to drag around everywhere. After a while, the IV stands are phased out, and the bags gain eye holes (albeit black ones that cover up the actual eyes) and visible noses. The last ones before Bill gets her upgrade include a metallic skull cap, which Mr. Razor approves of.
  • Could Say It, But...: Razor begs Bill not to ask where the lift entrance is hidden because he would tell her. Bill promptly glomps him. "You know what I'm going to ask you."
  • Creepy Monotone: "Pain. Pain. Pain. Pain. Pain. Pain. Pain. Pain."
  • Curtain Camouflage: Bill attempts to hide behind a curtain in the hospital. Not very well, as her IV stand is still outside the curtain.
  • Cut His Heart Out with a Spoon: Missy threatens "Mr. Razor" with numerous colourful references to what she'd do to his internal fluids, organs and other parts if he keeps annoying her.
  • Cybernetics Eat Your Soul: The Cybermen's handles are revealed to be what inhibits their emotions, specifically so that they do not care that they are in constant pain. However, Bill Potts still seems capable of emotional distress as of the Cliffhanger, shedding a single tear as she reaches out to the Doctor she waited for so, so long.
  • Damsel in Distress: Bill ends up trapped, isolated, and facing Cyber-conversion, and the Doctor and his colleagues are desperate to save her.
  • Darkest Hour: As the first half of the Season Finale, this episode serves as this for the Twelfth Doctor, Bill, and Nardole as two of the Doctor's three mightiest enemies team up — in more ways than one, at that.
  • Dashed Plot Line: The next episode confirms that Bill's scenes once she gets to the other end of the ship unfold over ten years total, though how much time passes from scene to scene is not specified. In any case, it's enough time for the design of the first generation of Cybermen to be perfected and for Bill to become Conditioned to Accept Horror as she waits for the Doctor to get there. Saxon will claim in the next episode that the Doctor arrived twenty minutes after Bill was converted into a Cyberman.
  • Death by Irony: Bill is scared of and distrusts Missy, the present-day version of the Master who appears to honestly intend on turning over a new leaf and helps the Doctor in his attempt to rescue Bill, but ultimately gets tricked and lead to her fate of cyberconversion by Missy's previous and still-evil past self, whom Bill had befriended.
  • Distress Call: How the Doctor finds out about the crippled spaceship and chooses it as the place to test Missy.
  • Dramatic Irony: Even fans who somehow managed to miss the worst-kept secret of the season or just don't recognize the very first incarnation of the Cybermen will recognize what's been one of the Cybermen’s Catch Phrases for the entire new series. However, poor Bill is too new a companion to know enough to say Oh, Crap! like we do when people being "upgraded" is mentioned.
  • Dramatic Unmask: As you do when you're an Arch-Enemy wearing a Latex Perfection disguise.
  • Driven to Suicide: Bill makes the mistake of turning up the volume on a second incomplete Cyberman who is a Broken Record like the first. It's not saying "Pain." It's saying "Kill... me..."
  • Dying Alone: The fate of the Twelfth Doctor, who is alone as he begins to regenerate in the pre-credits scene. And to make matters worse, he's not even regenerating inside the TARDIS this time, who could ostensibly be considered sentient, and has his back turned to the police box, so he really is dying alone.
  • Dying Race: The Mondasians descended from the crew can no longer survive in the tail end of the ship, having nearly exhausted the resources available to them. Everything is rusting and the air filtration system is being choked by engine fumes. To survive, they are "evolving" into the first generation of Cybermen. On the other hand, the Master is there, so who knows what could have been.
  • Emerging from the Shadows: Used for The Reveal when the Doctor sees a pair of boots standing in a dark alcove, from which steps a Mondasian Cyberman.
  • Escape from the Crazy Place: Bill would really love to, she just can't because Razor won't tell her where the lifts are, and even if he did, her artificial heart won't work long outside the hospital.
  • Evil Counterpart:
    • As Mr. Razor, the Master is an evil counterpart to the Twelfth Doctor where their relationships with Bill are concerned. (Each one even has their own office.) The Doctor is a Time Lord who doesn't have the most amiable personality, but he's lifting up a human woman supposedly "beneath" his station and encouraging her to be curious, outraged, compassionate, brave, and wise by teaching her all about the universe. The Master disguises himself as a poor nobody (reflecting how he sees her) and discourages all these things so that she may be Conditioned to Accept Horror and never try to find her own way out of the hospital. He only teaches her enough to convince her that the only hope the Mondasians have is what turns out to be Cyber-conversion, and to accept her similarly gloomy fate and never hope/want more. He lets her know the Doctor is coming via the TV solely to make his betrayal that much crueller; because she wasn't curious and brave enough to seek out the lifts herself, she has to ask the Master for help when the Doctor finally arrives. He is kindly and amiable as Mr. Razor in a way Twelve wasn't, but he's the one who ultimately strips her of her agency altogether and transforms her into a cyborg slave.
    • For that matter, Saxon Master effectively turns Bill into a twisted variation on Nardole, the Twelfth Doctor's cyborg companion. Thanks to the Doctor's efforts, Nardole retains his agency and a humanoid appearance, serving as a Morality Chain who isn't afraid to call the Doctor out. The Master "gives" Bill an ugly Mondasian Cyberman body and leaves her with dampened emotions and little free will, a perfect "companion" for someone like him: obedient, unquestioning, and disposable. Which is also important — the Doctor is always ready to lay down his life for companions, but the Master prefers to save his own skin.
    • It also makes the past Master his future self's evil-er counterpart: both play a not-so-nice version of the Doctor role, but Missy's is humorous; Mr. Saxon's is very twisted.
  • Evil Is Petty: The Harold Saxon Master has Bill turned into a Cyberman not only to hurt the Doctor, but also to keep his future self from turning good.
  • Evil Plan: The Master spends ten years scheming with the Mondasian Cybermen creators to prevent his next regeneration's redemption.
  • Evilutionary Biologist: The staff of the hospital is made up of these as they work to keep their fellow Mondasians alive and thriving by any means necessary.
  • Exact Words: The Proto-Cybermen who take Bill state they'll "repair" her. They never specify how.
  • Expository Hairstyle Change:
    • John Simm's Master now has a mustache and goatee, as per the Roger Delgado and Anthony Ainley incarnations of the character. His hair is noticeably greyer too, suggesting that this story takes place well after the events of "The End of Time".
    • The Doctor's hair is noticeably longer and wilder in the Foregone Conclusion pre-credits scene than it is in the main action, suggesting that a significant amount of time will pass between his coming up with his plan for Missy and his regeneration. This is especially interesting in that the main action on the ship unfolds over an Extremely Short Timespan for him. (The cold opening was shot after most of the rest of the episode was, just two weeks before the episode premiered, possibly overlapping with production of the 2017 Christmas Episode. The earliest preview screeners did not include the scene at all, both because the special effects weren't finished and to avoid spoilers.)
    • Weirdly averted with Bill, whose hairstyle doesn't change a bit in several years!
  • Extremely Short Timespan: The main action of this episode unfolds in less than an hour or so — for the Doctor, Nardole, Missy, and Jorj, that is. Once Bill is separated from them and stuck in the hospital on the end of the ship where time is running much faster, years elapse for her.
  • Eye Motifs:
    • The Doctor believes that if Missy could truly see the beauty of the universe, she would stop trying to destroy it.
    • The camera zooms in on the cloth eye of the Mondasian Cyberman whom the Doctor discovers in the hospital to the eye of Bill Potts within it. And a single tear of hers seeps through the Cyberman eye to close out the episode.
  • False Friend: Mr. Razor — really the Harold Saxon Master — is one to Bill, playing her like a fiddle the whole time.
  • False Reassurance: Bill's final words as a human.
    Bill: But look at them! They're screaming every second they're alive!
    Surgeon: But we've got something for that now! [holds up Cybermen handlebars] This won't stop you feeling pain, but it will stop you caring about it. It fits over your head.
  • The Farmer and the Viper: The Doctor is testing whether Missy fits this trope or not with regards to her capacity for good and their relationship, finding that she does when she (apparently) becomes part of the Villain Team-Up.
  • Fascinating Eyebrow: The Doctor in Sarcasm Mode. Bill and Razor have to watch a whole week of it.
  • Fate Worse than Death: Jorj doesn't know what happens to the humans that the Proto-Cybermen take; he just knows that it'd be better for them if they die rather than be taken — and he does have a point. Poor Bill ends up suffering this as a Mondasian Cyberman.
  • Five-Second Foreshadowing: Missy threatens to turn Mr Razor's organs into soup if he doesn't tell her what's going on. Razor replies by saying she would "never be so self-destructive. But then, neither would I." Seconds later, he removes his mask, revealing himself to be Missy's former self.
  • Foe Romance Subtext:
    • From the Doctor when he admits the Master was his first "man crush" (which could be Homoerotic Subtext, depending on which gender the Doctor was at the time).
    • Missy lampshades the trope (and she's not even referring to the Doctor).
      Missy: Deary me, I thought you were handsome, and now you've gone all cross and you're pointing a gun at me. Is this the emotion you humans call spanking?
  • Foreshadowing:
    • Bill's back in her denim jacket from "The Pilot", but alongside its "Wow!" patch there is now a skull patch, foreshadowing her being Killed Off for Real — not unlike Clara's raven necklace ended up doing for her.
    • The creepy surgeon tells Bill "the full conversion wasn't necessary" right after she arrives, "though it will be in time".
    • When Mr. Razor is thanked by the Surgeon for tricking Bill in to the Operation Theater, he comments (while wearing a burglar mask) "You saw through my disguise..." It turns out that he is actually the Harold Saxon Master wearing a Latex Perfection disguise.
    • Mr. Razor tells Bill that the patients aren't in any pain, which Bill quickly contests, at which point he concedes that it was "A clever lie." The last time we heard those words, they were spoken by the Eleventh Doctor in "Let's Kill Hitler", hinting that Mr. Razor has a connection to the Doctor.
    • In telling Bill that the proto-Cybermen are (or were) human, Mr. Razor gets stuck on the word "people", repeating it in a rapid-fire manner that's very similar to how the Horror Hunger-ridden Saxon Master ranted about food in "The End of Time".
    • When we first see the lift approaching the flight deck, the numbers on the indicator are moving really fast, but start to slow considerably as they near the top of the ship. It isn't decelerating, at least not in the conventional sense. It's a hint of the Time Dilation.
    • The first time we hear the modified voices of a "converted" patient calling out about pain, the voice, though unlike modern Cybermen, harkens back to how they sounded in "Tomb of the Cybermen".
    • Bill's fellow "patients" have cloth covering their faces and speak in a robotic tone, an early indicator of what is in store for her.
    • Razor mentions an expedition to the solar farms on Floor 507 that never returned. We find out what happened to them in the next episode.
    • Both Missy's going incognito as "Doctor Who" and the Doctor's comment to Bill about Time Lords being billions of years past our limited ideas of gender prefigure the Doctor's actual Gender Flip in a few episodes' time.
  • Foregone Conclusion: The pre-title sequence depicts the Doctor, looking dishevelled and anguished, stumbling out of his TARDIS onto a snowscape, falling to his knees, and beginning to regenerate.
  • For Your Own Good: The terrified Bill is told that her Cyber-conversion is the only way to permanently cure her fatal injury. If she disagrees, too bad.
  • From Bad to Worse: Again and again! Missy's attempt to be the Doctor and get the spaceship out of the black hole goes awry, and Bill ends up shot and trapped on the other end of the ship, having to wait years for rescue by the desperate Doctor thanks to Time Dilation. Then it turns out she's specifically trapped with people who are busy becoming what will eventually be the first generation of Mondasian Cybermen.She's going to be "upgraded" too. Oh dear, turns out Missy's previous incarnation has something to do with all this. Oh no, Bill's become a Cyberman! Missy and the Master end up posed on either side of what used to be Bill, and she refers to him as "the ex" as if they might be teaming up!
  • Future Me Scares Me: The Master is very worried about his future self because she's trying to make a Heel–Face Turn, and this is the Ax-Crazy version of him. He then throws a monkey-wrench into those plans by turning Bill into a Cyberman, certain that the Doctor will always hate him — and Missy — for that. He's also trying to tempt his future self into a relapse back into evil because of how good it feels to be bad, and there's an insinuation that he's a bit taken aback at the thought of becoming female for the first time.
  • The Gadfly: Missy riffing the Doctor's vain, arrogant and sentimental performance as The Hero. The companions are just there as replaceable amusements or someone he can explain things to, and Missy even claims that the Doctor used to call himself "Doctor Who" before realising it was a bit too much (the Doctor says she's making that up).
  • Generation Ships: The Mile-Long Ship is large enough to contain cities and forests, and many, many people... namely, the dying Mondasians. The twist is that none of the residents of the lower decks are the intended colonists! They're actually all descendants of the 20 crew members who went downstairs over 1000 years ago (from their perspective) just to put the engines in full reverse in order to try and escape the black hole. Meanwhile, due to Time Dilation, only two days have passed on the bridge deck, leaving the sole remaining crew member very confused as to the sudden population growth.
  • Gender Is No Object: When reminiscing about his youth on Galifrey, the Doctor wonders what genders he and the Master were back then but thinks both are irrelevant. He says that humans have a "petty obsession" with fixed genders.
  • The Glomp
    Razor: When you hug me, it hurts my heart.
    Bill: Ah, sweet.
    Razor: No. Your chest unit. It digs right in.
  • Gone Horribly Wrong: The Doctor's effort to redeem Missy quickly takes a bad turn, and it's Bill who pays the most for it.
  • Grand Finale: This episode is the beginning of this for the Twelfth Doctor and the Steven Moffat era, continuing directly into the Season Finale "The Doctor Falls" and from there — albeit after a gap of nearly six months — the Christmas Episode that serves as his regeneration adventure.
  • Heel–Face Turn: After showing signs of this since "Extremis"; Missy seems ready to fully make one of these. The Doctor decides to test her sincerity, but John Simm's version of the Master is around and wants to prevent her from reforming.
  • The Hero Dies: The Foregone Conclusion — the Twelfth Doctor regenerates for some reason thanks to the events of this story.
  • History Repeats:
    • As in the Series 9 finale storyline ("Face the Raven"/"Heaven Sent"/"Hell Bent"), the Twelfth Doctor seems to have no hope of saving his companion from being Killed Off for Real, if only to save them from a Fate Worse than Death. Or does he? Tune in next week...
    • Also, as in the Series 8 finale storyline, the Doctor has no hope of saving a character from being Killed Off for Real (or does he?)note  and a new character is revealed to be an incarnation of the Master, and then... enter the Cybermen!
    • Like Rose in the Series 1 episode "Dalek", Bill is not familiar enough with a recurring enemy to realize the danger she's in until it's too late, with the audience catching on long before she does.
  • Hope Spot:
    • The Doctor gives a reassuring speech to Jorj, similar to the one he gave the survivors of Chasm Forge in "Oxygen", telling him he will solve the crisis of the ship and asking him to stand the gun he's aimed at Bill down. Jorj wavers a bit, and Bill even starts lowering her raised hands... then the lifts arrive and he plugs her in the chest.
    • As the Doctor and friends board the lift at last, Mr. Razor offers to show Bill where they'll be getting off. But it's a trick to lead her into the conversion theatre, where she is to be completely Cyber-converted.
    • The Doctor has one when he questions the Cyberman as to where Bill is. It accesses its memory banks... and then says a Wham Line revealing it to actually be Bill Potts.
  • Hostage MacGuffin: Bill Potts. The Doctor and company are trying to get the spaceship out of the black hole, but once she's shot and hauled off to the other end of the spaceship by the Proto-Cybermen their concern becomes getting there to rescue her since they know she won't be returned. Notably, at the end of "The Doctor Falls" the ship is still stuck as far as the audience knows.
  • How We Got Here:
    • The cold opening begins with the Doctor staggering out of the TARDIS onto a frozen planet, but before he can get anywhere, his hands start glowing orange, and he begins to regenerate... cue a two episode-long flashback.
    • The episode proper begins with Missy and her "disposables" arriving on the ship in response to the distress call, before a flashback explaining why the Doctor brought Missy along and allowed her to do his job.
  • Hypocritical Humour
    The Doctor: We're the most civilised civilisation in the universe. We're billions of years beyond your petty human obsession with gender and its associated stereotypes.
    Bill: But you still call yourselves Time Lords?
    The Doctor: Yeah... Shut up.
  • The Igor: Mr. Razor has overtones of this before his true identity is revealed; the stump, the forehead, the speech patterns and servile position in a Mad Science project — all of it.
  • Internal Reveal: Bill learns Missy used to be male.
  • It Seemed Like a Good Idea at the Time: To the Doctor, anyway. To test Missy's sincerity with regards to her apparent Heel–Face Turn the Doctor, having previously ensured she cannot tamper with the TARDIS controls, brings her to a place in need of help and tasks her to take his place and solve the crisis. He entrusts his wary companions, who both tell him this is an awful idea, to her care. He watches and coaches them from within the TARDIS, which is in the same room with them in case worst comes to worst and he needs to join the fray. But it turns out the first person Missy encounters is terrified of Bill Potts's presence, Missy doesn't handle it well, the Doctor can't de-escalate things — and everyone's on the road to catastrophe. (In his defence, it's hard to imagine any way to prove Missy's sincerity that wouldn't run some kind of risk, and blindly trusting her is not an option. He can't just keep her locked up forever as per his original vow — it hasn't been good for him or her — and killing her would violate his morals.)
  • I Warned You: As Jorj points a gun at Bill she tells the Doctor "I told you this was a bad idea", referring to his ploy to test Missy's sincerity by having her take his place. Barring a miracle, these are the last words she will ever speak to him as a human.
  • I Will Find You: Bill has visions of the Doctor telling her "Wait for me", and indeed he is doing everything he can to reach her end of the ship and rescue her.
  • Kick the Dog: Razor/The Master betrays Bill in the cruellest manner possible, befriending her for years, only to betray her when Bill thinks she's finally on the verge of rescue.
  • Lack of Empathy: The hospital staff simply doesn't care about the agony the Proto-Cybermen are in; to them it is enough that they are alive. The Nurse's response to one of them begging for help is to turn down the volume on their voice unit.
  • Lampshading:
    • Missy calls herself "Doctor Who" to save time with the whole Title Drop Running Gag.
    • Missy labels her "plucky assistants" as "Exposition", "Comic Relief", or "Disposable".
    • Missy's "Darling, those were genders" lampshades the fact that, once Dashing Leading Man was occupied by the Doctor himself, the roles of Exposition and Comic Relief were attached to the female and (when present) male companions respectively.
  • Large Ham: Missy as "Doctor Who", starting from the moment she leaves the TARDIS.
  • Late to the Tragedy: By the time the Doctor and his friends arrive at the spacecraft, the Mondasians at the rear end of the ship where time moves faster have been suffering the effects of Time Dilation for thousands of years, starting their journey to becoming the Cybermen.
  • Latex Perfection: Like Delgado and Ainley's Masters, Simm's makes use of a realistic rubber mask to disguise himself.
  • Leitmotif:
    • Just as the man talking to Missy reveals who he really is, the four-beat theme associated with the Master in RTD's era starts playing alongside, and again in the final scene.
    • The swelling buildup to the first time we hear it in "Utopia" (when Jacobi's version of the Master regenerates into John Simm's version) is heard in Mr Razor's office, and when Mr Razor says "Ah, so you don't know."
    • The Master's actual leitmotif, a six-note melody that spells out his name in musical form ("The Mah-ster! The MAH-STER!") is heard as a short, playful variation as Mr Razor first leads Bill through the hospital corridors.
  • Like an Old Married Couple: Before it all goes wrong, Missy and the Doctor have got to this stage from both sides, him bugging his friends to be her pretend companions, and her snarking at him to not test her eating crisps (which he quickly puts aside).
  • Literary Allusion Title: It comes from Andrew Marvell's "To His Coy Mistress", a romantic poem about seizing love while one can, which has such lines as "Nor, in thy marble vault shall sound/My echoing song". The Doctor's Arch-Enemy Missy (whose name is short for "The Mistress") has been key to this season's Story Arc, and she's been imprisoned in a vault. The poem also refers to mortality (the Cybermen were created to prevent death), while the poet talks of how if he was immortal the coy refusal of the poet's affections would not matter as he could take forever to woo her, which seems to fit Missy's view of her relationship with the Doctor.
  • Little "No": Followed by a Big NOOOOOOOOOOOOOOO! as the Doctor tries to hold back his regeneration.
  • Long Bus Trip: It has been nearly seven years since we last saw the Simm Master. It's been considerably more since we've seen the original "Tenth Planet" version of the Cybermen.
  • Look Behind You: The Doctor points and shouts, "Look!" then aikido-flips Jorj when he does so.
  • Madness Mantra: Anything said by those undergoing Cyberconversion, whether screaming in pain in a Creepy Monotone or calling for someone to Mercy Kill them.
  • Medical Horror: The hospital embodies this concept — most of the patients awaiting their surgeries are identically masked, the staff is sinister, the noises from afar are chilling, the lighting is low...
    Patient: [via keypad] pain pain pain pain pain pain
  • Meta Girl: Missy takes on this role when she dissects (and lampoons) the typical formula of the Doctor and his companions in a nutshell.
  • Mile-Long Ship: The ship is 400 miles long and 100 wide, which is a lot of mass to be trying to drag out of a black hole.
  • Mood Whiplash: Twice over in less than ten minutes.
    • Missy's attempt at being the Doctor is blackly comic fluff before matters escalate and Jorj aims his gun at Bill.
    • Things are finally calming down from that moment before Jorj fires and we see a gaping hole in Bill's chest.
    • In the wake of the horror of Bill's shooting, there's a flashback that begins with a humorous montage of the Doctor pestering Bill and Nardole with his idea for testing Missy over the course of several days. This is especially pronounced in BBC America airings, which put the first commercial break right between these two sequences.
  • Motifs: Series 10-specific:
    • Promises: The Doctor never did fulfil a pact he made with Missy to visit every star in the universe together, but sees such a journey now as holding the potential for redeeming her. Bill asks him to promise her that, as Missy's companion, she won't be killed. He cannot do that, although he says he'll protect her "Within reason." Unfortunately, his efforts turn out to be for naught; while she does survive being shot, she ends up undergoing a Fate Worse than Death.
    • Imprisonment/Release: Missy is released from the TARDIS at last to see if she can be the Doctor in a given situation. Bill ends up stuck in a hospital that is, ultimately, busy converting Mondasians into Cybermen, and finally is turned into one herself, a prisoner of what keeps her alive.
    • The value of individual lives: Bill is important enough to the Doctor that he is desperate to save her even with everything else going on.
    • Hidden threats: The Doctor and company are trying to get a spaceship out of a black hole, but it turns out the Mondasian Cybermen are in the making on the other end of the ship. And Mr. Razor, Bill's only friend in the hospital, is actually the Harold Saxon Master.
    • "Villains" that aren't actually evil: Jorj is fearful of humans (and shoots Bill Potts) because of the horrors the Mondasians are up to on the other end. Bill comes to understand that the Mondasians just want to survive; it's just that they're gradually becoming the first generation of Cybermen, not knowing what their kind will eventually "evolve" into. And Bill, the Doctor's dear, pure-hearted companion, ends up upgraded herself.
    • Exploitation: Many, many desperate Mondasians serve as guinea pigs for the Evilutionary Biologists who ultimately create the first Cybermen, one of whom is Bill Potts.
    • Mothers: Mr. Razor claims that Bill is like a mother to him... or an aunt. She's rather creeped out by this.
  • Mr. Exposition:
    • The Doctor explains the concept of Time Dilation to his colleagues and the viewers, while Mr. Razor explains the Backstory of the Mondasians and why they're doing what they're doing now. Interestingly, despite The Reveal that Mr. Razor is actually the Master there is no reason to think (at this point) that he lies to Bill about anything aside from who he is.
    • Lampshaded by Bill (regarding the Doctor) and Missy (regarding companions).
  • Must Make Amends: The Doctor is desperate to save Bill by way of making up for his testing of Missy unintentionally imperiling Bill's life. Alas, she has been turned into a Cyberman by the time he reaches her... and a much bigger crisis is looming for him. Now what?
  • My Future Self and Me: For the Master, as Harold Saxon meets Missy.
  • My God, What Have I Done?: When Bill is imperiled thanks to his plan to test Missy's sincerity going awry, the Doctor feels he Must Make Amends.
  • Mythology Gag:
    • Missy calling herself "Doctor Who" is reminiscent of how, in the Classic Series, from "An Unearthly Child" until "Logopolis", and in the New Series, from "Rose" until "The Christmas Invasion," each Doctor's actor was listed as "Doctor Who" in the credits.
    • The Master calls this the "Genesis of the Cybermen", echoing "Genesis of the Daleks".
    • The Cyber-converted Bill's single tear at the end echoes the teardrop-like eye adornment that is a feature of several later Cyberman face designs, and it also recalls Yvonne Hartigan, the first Cyberman to retain her human self and survive.
    • Missy refers to Bill and Nardole as her "assistants," and when they object, she wonders if the right word is "companions," along with other less flattering options. The "assistant" vs. "companion" debate arose amongst the fandom when the revival series started. The debate was previously addressed in "School Reunion," when Classic Who companion Sarah Jane met then-current companion Rose.
  • The Nicknamer: Missy, who is claiming to be the Doctor, calls Bill and Nardole "my disposables, Exposition and Comic Relief." When Nardole objects to their being referred to by their functions, Missy explains she was referring to their genders. Prior to this, she also refers to them as "Thing 1 and the other one." Oh, the Doctor calls them something else doesn't he — "snacks", is that it?
  • No Good Deed Goes Unpunished: Bill comes to understand why the Doctor is so desperate to redeem Missy and agrees to aid him in his risky test for her, despite her fears. For this, she ends up shot, stranded for years, and ultimately converted into a Cyberman.
  • No Name Given: The surgeon and nurse Bill encounters in the hospital have no given names.
  • Noodle Incident: Apparently, Nardole used to be blue, or decided to become blue, then underwent a skin color operation where he changed/returned to being Caucasian.
  • Nothing Is Scarier:
    • The Mondasians aren't just "evolving" themselves because they're dying. They're also doing it to prepare for a fight with something several hundred floors above them, which we don't get to see.
    • The Mondasian Cybermen live in constant agony, and the earliest forms can't help but incessantly beg for death with their voice synthesizers. However, their whole bodies are covered, so all we can do is imagine what's been done to them underneath.
    • Bill never works up the courage to look at her artificial heart.
  • Nothing Is the Same Anymore: Bill Potts's conversion into a Cyberman means that even if she can retain her identity and the Doctor can get her to safety, she can't return to Earth and her old life — or go anywhere, really, owing to the reputation of Cybermen — unless he can find a way to restore her human form, and he's never been shown as capable of doing so before. This dilemma is explored further in the next episode.
  • "Not So Different" Remark: The Doctor freely acknowledges that he and the Master aren't that different; in fact it's the reason why they became friends in the first place. It's also a reason why he wants to redeem Missy now — if he can find and unlock the goodness in her, then it will prove he has goodness in himself as well.
  • Oh, Crap!:
    • Bill, after having a giant hole blasted through her torso, understandably has a look of total shock before she falls.
    • The Doctor, on realizing just where Bill is and what's become of her, followed mere seconds later by Missy entering the room with the old Master.
    • Missy gets a very large and horrified one when her past incarnation reveals himself in front of her.
  • The Only One Allowed To Kill You: Missy doesn't want the Doctor to rush into saving Bill, because if anyone kills him and it isn't her, "we'll both be disappointed."
  • Ooh, Me Accent's Slipping: Right before Mr. Razor reveals himself to be John Simm's Master, shades of Simm's normal, unaffected voice start to seep through.
  • Origins Episode: The origin of the main universe's Cybermen is revealed. Saxon even calls it the Genesis of the Cybermen.
  • Paper-Thin Disguise: Razor wears a domino mask when sneaking Bill into the surgery. It's subverted with The Reveal that he's wearing a far more effective disguise.
  • Parasol of Pain: Missy's umbrella is revealed to be a sonic device!
  • Playing Possum: The Cybermen lying slumped in the conversion room (allegedly failed experiments) are actually waiting to grab Bill.
  • Playing with Syringes: The first steps to creating a cyborg race involve a lot of... trial and error on the part of the hospital staff.
  • Plot Parallel: With this episode, Bill effectively undergoes the same experience Nardole did back in "The Husbands of River Song" and afterward: Volunteering to help with a risky plan, she ends up mortally maimed and to stay alive will need a new body. The Doctor ultimately managed to give Nardole a body that looks much like he originally did, and Nardole has retained his agency and independence. But because Bill fell into the Master's hands, she ends up trapped in a pain-wracked, hideous Cyberman body and has next-to-no agency left.
  • Polluted Wasteland: The Mondasian city has become one, and once its residents have been "upgraded", Operation Exodus is going to see them ascend to the higher floors of the ship to ultimately take back control of it.
  • Powerful and Helpless: The Doctor is the Determinator when it comes to keeping Bill safe, but even a Time Lord cannot do anything about Time Dilation and thus it takes years to reach her from her perspective... and he is too late. She has become a Mondasian Cyberman, and as of the Cliffhanger he doesn't give any indication that he knows what to do to reverse her transformation.
  • The Power of Friendship: The Doctor believes that his friendship could turn Missy to the side of good at last. They've been friends for ages.
  • Primal Fear: Bill's situation. Trapped in a hospital far, far from home for days, months, years on end, she is surrounded by all the Medical Horror one could imagine, her only hope of rescue is far, far away (temporally more than physically), and she has to go under the scalpel to keep on living...
  • The Promise: The pact the Doctor and the Master made to see every star in the universe was never seen through... but he believes the spirit of that promise might help redeem Missy. Bill is scared that she'll end up dead serving as Missy's companion for a day and asks the Doctor to promise that she won't be killed; he can't do that but he does agree to keep her safe "Within reason." And he tries to hold to that, but ultimately isn't able to save her from a Fate Worse than Death.
  • "Psycho" Strings: The John Simm version of the Master removing his disguise and revealing his identity to Missy features a series of these as background music. They're fairly quiet, but very ominous. Fittingly for a Cybermen episode, they're somewhat electronic-sounding.
  • Race Against the Clock: The Doctor is desperate to rescue Bill, but thanks to Time Dilation (as Steven Moffat's synopsis puts it) "For once, Time is the Time Lord's enemy..." because time is moving far faster on her end of the ship. How long can she hold out? Not long enough.
  • Reconstruction: The Nightmare Retardant Mondasian Cybermen with their silly sing-song voices, faces like carnival laughing clowns, overly bulky chest packs and headunits like handlebars are made to look creepy by showing the full horror of the cyberconversion process, with designs that reasonably evolved from a Medical Horror aesthetic.
  • Red and Black and Evil All Over: The Harold Saxon version of the Master now wears a black overcoat and pants, with red lining to the coat for what's both a sort of evil counterpart to the Twelfth Doctor's standard look and a throwback to Classic Who Masters.
  • Redemption Quest: The Doctor sets Missy upon one of his typical heroing missions, "go to a distress call and resolve the problem", but when it goes horribly wrong, he Must Make Amends, and she is encouraged to leave the quest by her previous self.
  • Retcon: "The Tenth Planet"'s Mondasian Cybermen retained human hands that were ungloved, but this origin story implies that they are artificial limbs with their uniformly masculine, surgical-gloved appearance. Peter Capaldi actually noticed and objected to this, but accepted the justification that if they didn't have gloved, masculine hands The Reveal (especially in-universe) that the first one is a converted Bill — a black woman — wouldn't work.
  • The Reveal:
    • The humans of the colony ship were from Mondas, and are becoming the Cybermen.
    • Those "handles" that come standard with Cybermen are actually emotion suppressors. By extension, that means they are to blame for the way Cybermen are so unfeeling and quick to destroy life that won't submit to upgrading in the present day, and this is the part of the Cybermen the Doctor has shorted out in the past to make Cybermen recognize their buried emotions.
    • Mr. Razor is actually the Harold Saxon Master. And Missy apparently forgot the events she experienced back then, which is why she failed to connect the dots.
    • Bill Potts has been turned into the first proper Cyberman.
  • Sadistic Choice: The Doctor is faced with either letting Bill die from her grave injury or placing his trust in the creepy strangers who arrive via the lifts to save her but not return her. Due to the nature of her injury he can't Take a Third Option by returning to the TARDIS and seeking out help elsewhere, and he cannot bear to let her die, so he chooses the second option. Unfortunately, he apparently doesn't think to board the lifts with them and learns all too late that their idea of saving her is a Fate Worse than Death.
  • Skewed Priorities: Even after he realises that the top of the ship is moving exponentially slower than the floor Bill is on, the Doctor stops to give a lecture on the subject, instead of racing the lift. The next episode reveals that Bill spent 10 years waiting for him to get her while he was showing off.
  • She Will Come for Me: Bill realizes that the Doctor will reach her in the hospital... eventually. Subverted in that by the time this happens, she's already been fully Cyber-converted. As this is something he's never been shown as able to undo, it leaves the question of what the two of them will do now in the Cliffhanger.
  • Shout-Out: Many viewers found "Mr. Razor", Saxon's alter-ego, reminiscent of Babylon 5's Zathras.
  • Single Tear: Cyberman Bill Potts sheds a tear from within her mask as the Doctor makes her realize who she once was.
  • The Slow Path: Thanks to Time Dilation, Bill ends up stuck on this waiting for the Doctor to come to the hospital.
  • Slow Transformation: Bill gets her artificial heart as soon as she is admitted into the hospital, which turns out to be the first step towards complete Unwilling Roboticization. Due to Time Dilation, it's possible that her final offscreen "upgrade" into a Cyberman took a while to finish, given that it takes a few minutes from the Doctor perspective to reach her once she's under the knife yet when he finds her the emotion suppressor and Hive Mind of the Cybermen has not already erased her personality.
  • The Snack Is More Interesting: Missy calls the Doctor on his eating chips while he's supposed to be instructing her on how to be him.
  • Space Opera: This two-part Season Finale is a rare example of Doctor Who indulging in this trope. It features our hero waging war against his arch-nemesis and his army of cyborgs in an absurdly massive spaceship with little focus on history, mystery, or ordinary time travel present in your average episode. This one is all about a big battle between good and evil in space.
  • Strapped to an Operating Table: Bill ends up undergoing this when Mr. Razor delivers her to the surgeons in the conversion theatre.
  • Stunned Silence: Upon realizing that Bill's been turned into a Cyberman, the Doctor is reduced to this, and nothing is able to break it as this is followed up by the two Masters revealing themselves.
  • Swapped Roles: The Doctor lets Missy play his role in the belief that it will improve her. Her calling her companions "disposables" shows she's got some work ahead of her, and when Bill is imperiled he has to join the fray.
  • Sympathy for the Devil: The Doctor knows that Missy/The Master was once a good person, the only person he ever knew who was exactly like him, and her evil and insanity were not entirely of her own making. He also knows that this particular incarnation truly wants to be his friend again, but is so mentally broken that she doesn't know how to win back his favour aside from trying to drag him down to her level via horrifying schemes (fulfilling the Hybrid prophecy by bringing him and Clara Oswald together, creating a Cyberman army of the dead and living to conquer the universe with...). He decides to try to raise her up to his instead, hoping that in finding and proving the good in her, he can find and prove the good in himself.
  • Sympathetic Villain, Despicable Villain: A rare case where the irredeemable and sympathetic villains are technically the same character. Missy, the latest incarnation of The Master whom the Doctor has been trying to teach to be good, is convinced by her previous "Harold Saxon" incarnation to make companion Bill undergo Unwilling Roboticization right before the Doctor can rescue her, just to stick it to him. But since Missy has shown remorse before and was not privy to Saxon's plan the whole time, the story frames it that there is still hope for her in "The Doctor Falls", proven true when Missy decides to stand with the Doctor after all, stabbing her previous incarnation. The Saxon Master kills Missy (and supposedly all future Masters) permanently for her Heel–Face Turn, hating the idea that he ever turns good in the future.
  • Take That, Audience!: While playing the role of the Doctor, Missy calls herself "Doctor Who" and insists that it's actually his real name. Doctor Who fans are well known for how seriously they take the Doctor's moniker, with outsiders referring to the character as "Doctor Who" being a huge Berserk Button. Therefore, this scene was likely Moffat's way of trolling the fandom.
  • Targeted to Hurt the Hero: Bill Potts may not be technically dead, but she has been turned into a Cyberman by Saxon and the hospital staff, and both he and Missy gloat as the Doctor stares in horror upon the friend he was so desperate to save. Saxon did this not only to break the Doctor's hearts, but to encourage Missy to give up her Heel–Face Turn, since how could the Doctor ever forgive her for this? And he succeeds on both counts, it would seem.
  • Then Let Me Be Evil: In the Cliffhanger, it appears Missy makes this choice upon learning that her previous self was responsible for Bill Potts becoming a Cyberman, apparently believing what Saxon suggests — that the Doctor cannot forgive her for this and will never see her as worthy of friendship again, leaving her no reason to be good.
  • This Is the Part Where...: Bill watching the Doctor on television.
  • This Is Unforgivable!: Saxon suggests to Missy that the Doctor will not be able to forgive her once he realizes what they did to Bill Potts.
  • Time Dilation: The plot pivots upon this concept. As the spaceship the Doctor and his companions are on is caught in the gravitational pull of a black hole and is trying to reverse its way out, time dilation affects it. Where 10 minutes pass at the Doctor's end, several years pass at Bill and the Mondasians' end.
  • Title Drop: In the first proper series' title drop (lack of question mark included) since "The War Machines" in 1966, Missy impersonates the Doctor while calling herself "Doctor Who", revealing that it was his first choice for a name in the Academy before he eventually dropped the "Who" and became known only as "The Doctor".
  • Tonight, Someone Dies: According to Steven Moffat's Radio Time synopsis, "the Doctor witnesses the death of someone he has pledged to protect." It's Bill Potts, who ends up with a hole in her chest. But as it turns out death is not the end...
  • Torso with a View: Jori's blaster puts a very large hole in Bill's chest, as a Wham Shot to show the audience that this particular shooting is not going to be easily resolved. The Cyber-converted from below deck show up to retrieve her and fit her with an artificial heart to save her life.
  • A Tragedy of Impulsiveness: The Doctor decides to test Missy's sincerity by swapping roles with her for a day. As Steven Moffat puts it in his video introduction, "The Doctor and Missy have been friends for an incredibly long time, and he wants more than anything else for her to be a good person, like him. And she’s starting to want that too. The consequences for that are going to destroy a lot of lives."
  • Trailers Always Spoil: To extremes, with many reviewers complaining about how much was spoiled, as most of these details are only slowly revealed. About the only twist not spoiled to some extent was the Doctor beginning his regeneration at the end of the story's events, which was shot just two weeks before the episode's airing and not included in the earliest preview screeners.
    • The return of the Mondasian Cybermen was one of the first official announcements made regarding Series 10 storylines.
    • The second Series 10 trailer (which appeared at the end of "The Pilot") and ALL episode-specific trailers gave away the return of the Harold Saxon Master. Granted, the U.K. tabloid The Sun leaked the news that John Simm was returning to the show, but Steven Moffat was not happy about this. And no wonder, as it gave informed viewers a big reason to be suspicious about Mr. Razor...
    • While the Next Time trailer avoided this by merely implying Bill would be shot (and not revealing how devastating the wound was), all other promos revealed Bill coming to in the hospital with machinery visible beneath her robe. Between this and the Cybermen's presence having already been revealed, not only did this spoil she would undergo Unwilling Roboticization to some extent, but also that the Doctor loses his Race Against the Clock to spare her from any kind of Nothing Is the Same Anymore fate and he thus Must Make Amends in another way. Worse, some people put this and the promo photos together and figured out how just far the conversion would get.
    • On the off-chance you managed to miss all of the spoilers about the return of the Cybermen, BBC America is more than happy to spoil it for you while the episode is airing. An interstitial intended to drum up interest for the next segment during the commercial break blatantly revealed both that the ship was from Mondas and that the Cybermen were appearing less than ten minutes before the reveal itself.
  • Two Lines, No Waiting: Initially the Doctor, Missy, Bill, and Nardole are all together, but once Bill is separated from them the story alternates between her experiences in the hospital and the Doctor, Missy, and Nardole trying to reach her before she comes to (more) harm.
  • Unrealistic Black Hole: Whilst you certainly would experience relative time dilation at different distances from a black hole, the extreme levels shown here are actually totally unrealistic whilst being so far from the hole itself. (Even a supermassive black hole, like the ones at the centre of galaxies, isn't massive enough to cause this kind of dilation whilst still at "just about able to escape" distance.)
  • The Unreveal: Missy claims that "Doctor Who" is in fact the Doctor's real name, having chosen it at the academy only to later drop the "Who" part. Bill asks the Doctor whether or not this is true; the group is interrupted before he can answer.
  • Unspoken Plan Guarantee: Just like Clara did in "Face the Raven" by explaining her plan to take on the chronolock to Rigsy, the Doctor fully explains his plan to test Missy to his companions... and thus it winds up completely failing.
  • Unwilling Roboticization: Bill undergoes this in the hospital, starting with her very own Cyberman prototype heart. It's safe to say she didn't agree to the full package, either, not that it stopped them. The degree to which the Mondasians are volunteering for this procedure is unclear, but the fact that some of them are begging for death suggests the scientists have stopped considering their wishes.
  • Unwitting Instigator of Doom: Jorj accidentally shot Bill, who ended up becoming the first Cyberman.
  • Villain Team-Up: The Mondasian Cybermen are now allied with two incarnations of the Master (Harold Saxon and Missy), the former of which helped bring them into being.
  • We Are as Mayflies: The Doctor is frustrated by Bill's reluctance to help him test Missy. When Bill suggests that Missy might just start mowing people down as soon as she steps outside of the TARDIS, he notes that humans "pop like balloons" compared to Time Lords.
  • We Used to Be Friends: The Doctor explains his relationship with Missy/The Master to Bill this way: "We had a pact. Every star in the universe, we were going to see them all — but he was so busy burning them, I don't think she ever saw anything."
  • Wham Episode: The poor Doctor loses Bill to Cyber-conversion and looks to lose his last chance at redeeming Missy to the allure of evil, on top of having to confront the Harold Saxon Master and the first generation of Cybermen... and all this is the beginning of the story of why he must regenerate into this thirteenth numbered self.
  • Wham Line: Take your pick!
    Computer: Scanning. Result Found. Mondas
    The Doctor: It's a Cyberman... a Mondasian Cyberman!
    Cyberman: ACCessiiiIIIiiing: Bill POTts. LOCAtiiiIIIiiing: Bill POTts. I-iiiiAM Bill POTts.
    Mr. Razor: Do you still like disguises? Of course, they are rather necessary when you happen to be someone's former Prime Minister!
    Cyberman: I-iii WAITed. I-iii WAITed forrrrr yoUUUUuuuuu.
  • Wham Shot:
    • The hole blown through Bill's chest is this in the most literal way.
    • The surgeon showing Bill that lovely little device they have for making the process she's about to go through so much less painful, unfolding it to show the distinctive shape of a Cyberman's handlebars.
    • The name of the ship's planet-of-origin appears on a video screen, overlaying an image of that world. And it's Mondas.
  • What the Hell, Hero?:
    • Bill and Nardole are not confident about the Doctor's plans for Missy, in part because they will have to serve as her companions for a day.
    • Bill gives one to Doctor after he finally makes it down to where she is, only to find out it's too late.
      Cyber-Bill: I-iii WAITed forrrrr yoUUUUuuuuu.
  • The World Is Just Awesome: The Doctor and the Master made a promise to see every star in the universe and the Doctor hopes this promise will help redeem Missy.
  • You Are Too Late: After thousands of years of the Doctor barging into a strange situation and talking down nervous gun-toting men who can't shoot straight, a companion gets shot dead. But still, the Doctor will save her Just in Time as always, right? Nope — thanks to circumstances beyond his control (Time Dilation and Saxon's cruelty), he ends up a few hours too late. To the Doctor's horror, Bill has become a Mondasian Cyberman by the time he reaches her. The real twist of the knife is that despite the time-dilation, despite years of waiting on her end, the Doctor arrived mere hours too late to save her from the conversion. Doing the math, that amounts to no more than a few seconds of wasted time on the bridge...
  • You Can't Thwart Stage One: The Doctor is too late to stop Bill from being converted into a Cyberman, and the beginning of the Mondasian Cybermen as a whole. Saxon also seems to triumph in his efforts to lead Missy away from her Redemption Quest.
  • Zeerust: The Mondasian Cybermen show up in all their shitty, low-budget 60's era glory. Justified in that they're being developed bit by bit across the years in a failing environment, jerry-rigged from scraps. Also, they're a bit better looking than the originals, and have an extra dose of Medical Horror to go along with it.