Death in Heaven (TV story)

Death in Heaven was the twelfth and final episode of series 8 of Doctor Who.

It saw the demise of Danny Pink, and the death of one of the two Osgoods. It revealed that Missy had been the "woman in the shop" who gave Clara the TARDIS phone number in The Bells of Saint John and the one who had provided the advertisement that drew the Doctor and Clara together again in Deep Breath. It also allowed Doctor Who to again pay homage to the late Nicholas Courtney, with his character, the Brigadier, appearing as a Cyberman. This was the first televised Doctor Who appearance by the character since Battlefield, and effectively his first televised appearance since Courtney's death. He had appeared in audios and The Sarah Jane Adventures in the intervening time period.

Death in Heaven, and first-part episode Dark Water, was shown in cinemas in 3D as a two-night event on the 15th and 16th September as a run-up to prepare for Series 9. It was followed by the premiere of the prequel scene The Doctor's Meditation. This screening was only shown in the United States of America, Canada, Denmark and Russia.

Synopsis
With Cybermen on the streets of London, old friends unite against old enemies and the Doctor takes to the air in a startling new role.

Can the mighty UNIT contain Missy? As the Doctor faces his greatest challenge, sacrifices must be made before the day is won.

Plot
Inside the 3W facility, Clara hides behind a desk as the Cyberman that had been Dr Skarosa marches out of his tank. However, it detects her, demanding she reveals herself. Clara complies, hands raised; she tells the Cyberman that she is a target of strategic value. The Cyberman scans her and states that she is Clara Oswald, an ordinary human with no value whatsoever. Clara tells the Cyberman it's wrong, that the identity of "Clara Oswald" is just a story she made up. Its interest piqued, the Cyberman asks for her identification again. Clara tells it that she is the one person who can change their face and hide in place sight in front of the Cybermen. When asked again for her identity, Clara claims to be "The Doctor".

Outside of St Paul's Cathedral, the Doctor tries getting everyone to run away from the Cybermen. However, sarcastically passes him off as a ranting madman. The Doctor is baffled by this sight; no-one is panicking at the sight of these silver monstrosities. Missy advertises the Cybermen as big metal men and charges the public one pound for a picture with them. Slinging an arm around the Doctor, Missy shows him pictures on her device which show that the same thing is happening globally.

When Missy states they should take a picture, an undercover Osgood offers to take a picture, seizing Missy's weapon. She calls in a strike, and UNIT officers reveal themselves from the crowd. Kate walks out of the crowd, introducing herself to the Cybermen, who dismiss her threats as insignificant as human technology cannot match Cyber-technology. With a smile, Kate tosses the empty head of a Cyberman from The Invasion in front of the Cybermen; they left that behind on their last attempt to conquer the Earth. The Cybermen use their rocket boots to escape. The roof of St Paul's opens and more fly out.

Missy reveals that there are ninety-one Cybermen. Osgood states that this is the number of areas of significant population densities in the British Isles, meaning one Cyberman for every town and city in the world. One Cyberman detonates itself above St Paul's, creating a dark cloud and deploying Cyber-pollen.

Meanwhile, in the Nethersphere, all the lights go out. Seb tells Danny that they all might be going home. He explains to Danny that he should think of the Nethersphere as a data-cloud for storing recently deceased minds. The good news, he says, is that their bodies have been "upgraded".

Back at St Paul's both Missy and the Doctor are sedated and the Doctor just manages to whisper to Osgood, "Guard the graveyards" before passing out. Kate states on the phone that the "first protocol" has been implemented as the cloud made by the Cyberman starts to rain into the graveyards – and only the graveyards. The water seeps out and makes the sewers and gutters overflow. The water gets into the Chaplet Funeral Home and animates the newly converted Cybermen within. One of these is revealed to be Danny Pink, who clutches the sheet of paper with his information on it.

Meanwhile, the Doctor wakes up in a UNIT aircraft hanger with the TARDIS as Kate informs him that protocols are in place and his co-operation is to be ensured since UNIT assumes that he won't automatically do so. The Doctor asks for Clara and Kate says that he just has to give the order, as soon as he is on the plane his word is literally law. The plane is revealed to be Boat One. Kate tells someone on the phone that the President is aboard and when the Doctor comments on the uselessness of Americans, Colonel Ahmed reveals that the President of the United States was not being referred to; instead they were talking about the newly inaugurated President of Earth, commander in chief of all armies on the planet with complete authority in every nation. 'That your solution for everything? Vote for an idiot?" the Doctor asks. And to his shock, Ahmed reveals the Doctor just insulted himself.

Back in St Paul's, Clara displays an incredible knowledge of the Doctor, trying to convince the Cybermen that she is him. She even offered to reveal his true name, however, another Cyberman arrives telling the other three both the lie and its cause. He looks down when she says that she is an incredible liar. He then knocks her unconscious and kills the other three who realise that he is not under Cyber-control. He is revealed to be Danny, as his unused hand is still clutching the piece of paper from the morgue.

As Missy wakes up, the Doctor asks her why she is alive and she states that he saved her, with Gallifrey being collateral damage. She then reveals that she knows where it is but refuses to give him this information as seeing him in agony of not knowing fun. As he leaves the Doctor reminds her of all those times she wanted to rule the world and calls it a piece of cake. Osgood quickly guesses who Missy is and brings the Cyber-clouds to the Doctor's attention, specifically the fact that they have expanded and now cover all land-masses. In response, the Doctor offers her a position in the TARDIS. The Doctor is called back to the office. Taking a moment, the Doctor mocking tells Missy "You know all those times you wanted to rule the world? Piece of cake." It is revealed that Cybermen have been climbing out of graves the world over.

When Clara wakes up, she finds herself in a graveyard just as Cybermen start climbing out of their graves.

On Boat One, a council discusses the graves, finding that though only a handful of Cybermen had come out yet, many more were hatching. Seeing Missy sticking her tongue out at him on the monitor, the Doctor realizes what the entire point of the 3W Institute was; it was to provide the Cybermen with a much more efficient method of adding to their ranks. Not only does this Cyber-pollen allow them to convert the dead, it can even convert children into Cybermen when they were previously only used for Cyber-Planners due to being too small for a typical conversion. Addressing Colonel Ahmed, a pessimistic Doctor says "Throw away your guns, Man Scout. How can you defeat an army that can recruit the dead?"

Meanwhile, all the Cybermen in the graveyard that Clara is in are fully out as they wander aimlessly.

Onboard Boat One the Doctor notes that these new Cybermen are not attacking since they are newborns; their software hasn't fully linked with the Cyberiad, thus they are harmless until attacked or given orders. Kate reveals that they had been investigating 3W for a while before they got a tip-off from a woman with a Scottish accent – Missy, the Doctor guesses, since she likes to show off her madcap schemes to the masses. The Doctor reveals that Missy has been uploading minds in the Nethersphere for as long as humanity has had a concept of an afterlife.

While this is happening, Missy attempts to gain Osgood's attention by singing a version of "Hey, Mickey" replacing Mickey with Missy. She whispers a secret in her ear in a distinctly Scottish accent — "I'm going to kill you in a minute." She refers to this as her "secret girl plan". She starts a countdown from ten while mocking human lifespans, before revealing that she had already escaped her restraints. She then kills her guards and Osgood before thanking her for being 'yummy'. She presses a button on her bracelet which causes a horde of flying Cybermen to attack the plane.

In the graveyard, Clara finds the Cyberman that brought her there - Danny. She tells what she thinks is just a drone that the Doctor will come for her, but Danny states he will not come. Defiant, Clara says that she believes in the Doctor, who has never let her down; she says he is the one man that she would never lie to. Shaking, Danny drops the piece of paper from his hand and raises his blaster, scaring Clara. However, he forces his arm down; though he's in pain from Clara speaking so fondly of the Doctor, he loves her too much to hurt her. He takes the mask off his helmet, revealing his face to be highly mutilated by the cyber-conversion. Crying, he asks her to turn on his emotion inhibitor.

Meanwhile, back on Boat One, Missy prompts the Doctor to ask her about her plan, promising that he will be surprised. She claims that by investigating those that die to save him she has realised that he wants to know that he is like her. The TARDIS phone begins ringing and Missy reveals that she both gave Clara the TARDIS' phone number (pretending it was for a PC helpline), and placed the advert in the Victorian newspaper. She claims that it was the only way to make sure the two deeply-opposite personalities — a control freak and a man who can never be controlled - stayed together.

The Doctor answers the TARDIS phone; Clara has called to tell him about Danny; she's opened the logo on his chest, but can't figure out how to turn on the inhibitor. He warns her not to turn on the inhibitor, because Danny will revert to a mindless Cyberman and kill her if she does. Meanwhile, the Cybermen are breaking into Boat One and killing crew members. Clara begins to hit switches around Danny's power core, hoping to find the inhibitor switch.

On Boat One, Kate has alerted other organisations of their situation and rushes into the room, saying that the plane is going down. Missy turns her attention to her and says that she likes Kate before blowing out a section of the wall, sucking her out of the plane. She orders the Cybermen to destroy the plane and teleports away, leaving the Doctor.

Boat One explodes and the Doctor is thrown clear of the debris. Seb and Missy watch on from the Nethersphere, remarking on how boring his death will be. Using his key to summon the TARDIS, the Doctor manages to catch and enter his ship before reaching the ground. Seb is excited over the turn of events, to which Missy replies that Seb is merely an AI. Seb continues to be enthusiastic before Missy promptly destroys him.

The Doctor materialises in the graveyard and warns Clara that if she deletes Danny's emotions, he will kill her. He denies that he will, and the Doctor says that the difference between himself and Missy is emotion; "pain is a gift". He tries to get Danny to tell him what the cloud will do, but Danny says he isn't fully integrated into the Cyber hivemind and cannot see. Danny then laughs that all of the Doctor's bravado just crumbled in the sight of a tactical advantage, mocking the Doctor as a typical officer who has to keep his hands clean.

Knowing how much it will hurt Clara, the Doctor sadly tells her that he has to know. Clara takes the Doctor's sonic screwdriver, telling Danny she loves him. Danny says the same, joking that he'll never say that again. Smiling through her tears, Clara turns on the emotional inhibitor. Danny stops smiling and goes blanked faced. The Doctor asks him what Missy's plan for the Cyber Pollen is. He tells the Doctor that the cloud will convert all of humanity into Cybermen. Anguished, Clara hugs Danny, who remains motionless.

Missy then teleports into the graveyard. Seeing Clara in agony, Missy offers to "pop away" the pain; however, the Doctor tosses Missy's device into the graveyard, already sick of the senseless murder. Missy apologises since she tends to get carried away; she tells the Doctor to cheer up as she came to give him a gift. Missy speaks into her bracelet, which controls the Cybermen. She then demonstrates plane safety tips and random movements. She then gives the Doctor the bracelet, allowing him the same control, as a birthday gift — "It's lucky one of us remembers," she notes. The Cybermen bow.

He refuses control of the army, but Missy points out the Doctor DOES want an army. With this army, the Doctor will now have the final say in the result of every great battle in the history of the universe. He can even save the people suffering in the Dalek camps and overthrow dictators; the universe would be at peace eternally. Tearing off the bracelet, the Doctor demands to know why she is doing this. Missy says she wants to show him that they are not so different; after all these centuries of fighting each other, she wants to rebuild their friendship. Seeing the Doctor panicking, Missy asks him if he can trust himself with this kind of power; if he can stay morally pure.

The Doctor takes a moment to reflect all every time he wondered if he was a good man since he asked Clara back in Into the Dalek. He suddenly has a realization and thanks Missy for helping him. He declares he is not a good man, nor a bad man, nor a hero, nor a president, nor an officer as Danny had described him. He says that he is "an idiot, with a box and a screwdriver, passing through, helping out, learning". He tells Missy that he doesn't need an army, as he has his companions. He points to Danny, stating that he would never harm Clara; love isn't an emotion, but a promise. Danny raises an arm and holds the crying Clara, much to Missy's shock.

The Doctor laughs that Missy didn't notice the only Cyberman not listening to her orders, right in front of her. "P.E. catch!" yells the Doctor as he tosses the bracelet to Danny, who promptly puts it on. Missy wonders what Danny will do. Danny states that the clouds will be burned. When asked by what, Danny states himself; Missy laughs, noting one burning Cyberman won't destroy the cloud. With a smirk, Danny tells Missy she's right.

Danny commands the Cybermen to attention. He tells them that this is earth's darkest day, but the dead shall save the land of the living. "This is not the order of a general, nor the whim of a lunatic. This is the promise, the promise of a soldier!" Danny turns to Clara, promising that she will "sleep safe tonight" before flying into the cloud with the rest of the Cybermen and destroying it, himself and the other Cybermen.

In the graveyard, Missy recites the coordinates of Gallifrey, claiming it has returned to its original location. Clara threatens to kill Missy with her own weapon; the Doctor takes it from her and prepares to do it himself to spare Clara. Seeing that she's finally brought the Doctor down to her level, Missy asks him to say something nice. With a sigh, the Doctor tells Missy that she's won. However, right before he can kill her, a blast from behind them hits her, seemingly disintegrating her.

A Cyberman is behind them. It lowers its weapon and points toward another section of the graveyard; Clara sees Kate Stewart lying there, still alive, muttering about her father. The Doctor, now understanding, turns back to the Cyberman, who he realises is Brigadier Lethbridge-Stewart, and remarks, "The Earth's darkest hour, and mine. Where else would you be?" before saluting him — Kate had previously remarked that her father's greatest wish had been to receive a salute from the Doctor. The Cyberman Brigadier then flies up into the sky, with the Doctor whispering "Thank you" after him...

Two weeks later, Clara awakes in the middle of the night to find a portal to the Nethersphere in her hallway. Danny speaks through it, saying that the Nethersphere is collapsing and that the bracelet only has enough power left for one one-way trip. Instead of coming through the portal himself, however, he sends through the young Afghan boy he killed, telling her to find his parents. Crying, Danny says he is sorry and the portal closes, leaving the boy in the hallway along with the broken bracelet.

The Doctor meets Clara in a restaurant, the latter remarking that he is two weeks late, an apparent improvement compared to previous errors. He notes she is wearing the bracelet and assumes Danny has returned from the Nethersphere; she tries to tell him he hasn't, but he thinks she is trying to say that she can't travel in the TARDIS anymore.

He says that it is fine and that he has found Gallifrey exactly where Missy said it was, and that, "for once, she wasn't lying". In fact, it is revealed that the Doctor travelled to the coordinates Missy gave him and found nothing but empty space. Closing the TARDIS door, he entered a fit of rage and attacked the console before sinking to the floor and weeping for his lost home planet. At the end of the day, Missy has had the last laugh.

However, the Doctor lies to Clara, telling her he found Gallifrey to make her believe that he will be fine without her. Hearing this, Clara changes her mind and goes along with the Doctor's belief that Danny has returned and that she too will be happy without the Doctor. Clara asks what he will do now; he says that Gallifrey can be a good place and that he will try to make it one. He says it's a long commute and Clara and Danny mightn't be able to make it.

They leave with a hug. Clara asks why he doesn't like hugging and he responds; "Never trust a hug. It's just a way to hide your face." As they hug, their faces each reveal their sadness behind each other's back. As the Doctor enters his TARDIS, Clara tells him that he made her feel special when they travelled together and thanks him for it. He thanks her "for exactly the same" and dematerialises the TARDIS while Clara walks away.

In a mid-credits scene, the Doctor is brooding alone in his TARDIS when he hears someone knocking at the door, telling him that "it can't end like this" and that neither Clara nor the Doctor is "okay". The voice turns out to be that of Santa Claus, who enters the TARDIS in a swirl of snowflakes and asks a boggling Doctor what he wants for Christmas...

Cast

 * The Doctor - Peter Capaldi
 * Clara - Jenna Coleman
 * Danny - Samuel Anderson
 * - Michelle Gomez
 * Seb - Chris Addison
 * Osgood - Ingrid Oliver
 * Kate Lethbridge-Stewart - Jemma Redgrave
 * Colonel Ahmed - Sanjeev Bhaskar
 * Boy - Antonio Bouroupael
 * Teenage Boy - Shane Keogh-Grenade
 * Teenage Girl - Katie Bignell
 * Graham - James Pearse
 * Cyberman - Jeremiah Krage
 * Voice of the Cybermen - Nicholas Briggs


 * Santa Claus - Nick Frost

Millennium FX

 * Prosthetics Effects Producer - Kate Walshe
 * Props Maker - Pete Fielding

Culture

 * Missy descends from the clouds with her umbrella opened, copying the title character in Mary Poppins.
 * Missy does an impression of Marilyn Monroe singing "Happy Birthday, Mr President".
 * Missy sings a version of Toni Basil's song "Mickey", replacing "Mickey" with Missy.
 * The Doctor calls the Valiant "Cloudbase". Osgood immediately says Cloudbase is from Thunderbirds, but Colonel Ahmed quickly corrects her with Captain Scarlet. In addition, the Doctor claims he and Sylvia Anderson, co-creator of both shows, shared at least one dance together.
 * The Doctor mocks Colonel Ahmed about being a Man Scout.

Individuals

 * Missy claims that she is giving the Cyberman army to the Doctor as a birthday present.
 * Danny's body was being stored at the Chaplet Funeral Home.
 * Kate Stewart declares herself divorced, mother of two children, a "keen" gardener, and an "outstanding" bridge player.
 * The Doctor recalls his friendship with the Brigadier, noting he would have given his old friend a salute if he had asked him.

Story notes

 * Clara's ruse to the Cybermen of claiming to be the Doctor in the pre-opening teaser was followed by a one-off modification to the title sequence, with the eyes of the Twelfth Doctor being replaced by those of Clara's, and Jenna Coleman's name preceding that of Peter Capaldi. This is the second time any aspect of the face of someone other than the Doctor in the title sequence. The first was the 1996 TV movie, which also featured the eyes of . This is also the first time where the name of the actor playing the Doctor is not the first name to appear in the title sequence, as Jenna Coleman's appears first.
 * The Radio Times programme listing was accompanied by a small colour head-and-shoulders photograph of Missy holding her weapon in her outstretched hand as the Doctor looks on, with the accompanying caption "Doctor Who / 8.00 p.m. Who are you? The Doctor is disturbed by the mysterious Missy in the series finale".
 * To keep the appearance of Santa Claus a surprise, Nick Frost was uncredited in Radio Times and on the BBC website.
 * This is the first episode to show a scene mid-end credits.
 * This is the first series finale to lead directly into the following Christmas Special since Last of the Time Lords.
 * This is the first reference of the term Prydonian since the 2005 revival of Doctor Who.
 * The episode continues the trend of the Cybermen appearing in each series' twelfth episode ever since Steven Moffat took over as showrunner. They also appeared in The Pandorica Opens, Closing Time and Nightmare in Silver, the twelfth episodes of series 5, 6 and 7 respectively.
 * Steven Moffat stated that Clara's reference to the Doctor being married four times included his marriage to Susan's grandmother. (DWM 482)

Ratings

 * 7.60 million (DWM 481)

Filming locations

 * St. Paul's Cathedral, London
 * Queen Street, Cardiff

Production errors

 * In the BBC iPlayer version of this episode, during the flashback scene featuring Rusty, the subtitles incorrectly credit his lines as being said by Davros.
 * As Missy drops her hat, someone hugs the Cyberman in front of her and squeezes its arm which makes the rubber costume fold in.
 * When Clara is on the phone with the Doctor, telling him about Danny being a Cyberman, the wide shot shows the chest piece that covers the emotional inhibitor on, even though he had already removed it prior.
 * When Missy has the side of the plane blown off, her wrist device is still on. When she tells the Cybermen to blow up the plane over Belgium, it's disappeared, but in the next shot, it's returned to her wrist.
 * When the Doctor prepares to kill Missy, he is clearly holding her device in the wrong orientation, with the beam emitters pointing towards the ground.

Myths

 * This would be Clara's last story. At one point, this was true. Up until shortly before production the plan was for Jenna Coleman to leave the series with this episode, however, she decided to return for the Christmas special and Series 9.
 * Clara is pregnant or dying. These two myths/rumours were sparked by the post-it note reading "3 months" seen in Dark Water, with the former also supported by the existence of Orson Pink in TV: Listen who is supposedly a descendant of Clara and Danny, yet Danny is now dead. Ultimately, the significance of "3 months" was never explained.

Continuity

 * The Twelfth Doctor does not know whether the Osgood he interacts with is the human or the Zygon copy. (TV: The Day of the Doctor, The Zygon Invasion / The Zygon Inversion)
 * Kate presents a damaged Cyberman headpiece to the Cybermen who emerged from St. Paul's Cathedral - a token from a previous attempt at invading Earth. (TV: The Invasion) The Doctor previously encountered the same model of Cyberman headpiece as an exhibit in Henry van Statten's museum. (TV: Dalek)
 * The Doctor again works with Kate Stewart (TV: The Power of Three) and Osgood (TV: The Day of the Doctor).
 * Missy shares the Doctor's view on human lifespans - that they are ridiculously short (TV: The Caretaker); while the Doctor says humans should be "in a constant state of panic", Missy says that humans are "born dying".
 * Missy's orders to the Cybermen in the graveyard mirrors how Mr Crane once ordered them likewise in the Cybus factory (TV: Rise of the Cybermen), as well as Miss Hartigan in Victorian London (TV: The Next Doctor).
 * The Doctor offers to take Osgood with him as a companion, but Missy kills her before he can make good on this promise. This isn't the first time someone was offered the chance to become a companion but died before they could take up the offer. Other invitees who died have included Lynda Moss, (TV: The Parting of the Ways) Madame de Pompadour (TV: The Girl in the Fireplace), Astrid Peth (TV: Voyage of the Damned), Clara Oswin Oswald (TV: The Snowmen) and Rita (TV: The God Complex). The Doctor also offered Jenny, his daughter created via genetic transfer, to become his companion. (TV: The Doctor's Daughter)
 * Missy tells Osgood to "say something nice" shortly before her death. She previously told Dr Chang to "say something nice" before his death (TV: Dark Water), and when cornered by the Doctor in the graveyard asks him to "say something nice" as she waits for him to shoot her.
 * Osgood has upgraded her attire of Doctor-clothes, now instead of wearing a multi-coloured scarf (TV: Robot to TV: The Horns of Nimon), she wears the Tenth Doctor's converse trainers (TV: The Christmas Invasion et al.) and the Eleventh Doctor's bow-tie (TV: The Eleventh Hour et al.), as well as a leather jacket, worn both by the War and Ninth Doctors.
 * When the Doctor first sees Osgood, he compliments her bowtie with "Nice bowtie". He previously complimented her scarf with "Nice scarf" upon first meeting her. (TV: The Day of the Doctor)
 * When the Doctor compliments her bowtie, Osgood says "bow ties are cool", a phrase he often used in his previous incarnation. (TV: The Eleventh Hour et al.)
 * The last time the Doctor made reference to his predecessor's bowtie, he described it as "A bit embarrassing." (TV: Time Heist)
 * Missy uses the phrase "Oh, my giddy aunt" when she is about to kill Osgood, a catchphrase frequently associated with the Second Doctor. (TV: The Krotons, The Three Doctors, The Two Doctors)
 * Neither Kate Stewart nor Osgood appear surprised at meeting yet another incarnation of the Doctor. (TV: The Day of the Doctor)
 * Osgood reveals that she knows that Missy is the Master and that she knows that the Doctor and the Master were childhood friends, (TV: The Time Monster, The End of Time, PROSE: The Dark Path) and that the Master had many times tried to take over the world. (TV: Terror of the Autons et.al.)
 * The Doctor later told Danny that he had a friend once that he thought was exactly the same as him, but it turned out to be wrong. (PROSE: The Dark Path et.al.)
 * Missy is tied to a chair while on the aeroplane. This draws a parallel to the Master previously being tied to a chair in Joshua Naismith's mansion. (TV: The End of Time)
 * The Master also had an army of Cybermen made from dead and dying humans. (TV: The Doctor Falls)
 * The Doctor calls himself an idiot. He previously called himself "Doctor Idiot". (TV: In the Forest of the Night) He also called himself an "idiot" and was thereafter called "idiot" by Panna. (TV: Kinda)
 * Clara asks the Doctor if he will steal a TARDIS and run away again after he goes back to Gallifrey. (TV: The Name of the Doctor) He later does this when he finally returns to Gallifrey. (TV: Hell Bent)
 * The Doctor kisses Missy, who previously kissed him. (TV: Dark Water)
 * The Doctor salutes the Cyber-converted Brigadier. He also twice saluted the Brigadier's daughter, Kate Stewart. (TV: The Power of Three, The Day of the Doctor)
 * The Doctor continues to hate when people salute him, however. (TV: The Sontaran Stratagem et al), though he accepted the Foretold's salute in Mummy on the Orient Express.)
 * Clara uses the identity of the Doctor for the second time. (TV: Flatline)
 * A news report mentions "accounts" on file of earlier appearances of the Cybermen. (TV: The Invasion, Army of Ghosts/Doomsday)
 * The same news report indicates that, prior to this incident, the name "Cybermen" was not actually widely known.
 * Osgood notes UNIT has files on all ex-Prime Ministers in reference to the Master's previous incursion, commenting "she wasn't even the worst". (TV: The Sound of Drums/Last of the Time Lords)
 * Missy reveals that she was the "woman in the shop" from whom Clara received the Doctor's phone number for Wi-Fi support, (TV: The Bells of Saint John) as well as being the one that left the hint in a newspaper which led Clara and the Doctor to ending up in the hideout of the Clockwork Droids. (TV: Deep Breath)
 * While masquerading as the Doctor, Clara claims many things from the Doctor's past, revealing that during her time with the Doctor she has gained intimate knowledge of his history:
 * She notes that among his family is a non-Gallifreyan daughter created via genetic transfer. (TV: The Doctor's Daughter)
 * She mentions the Doctor having children and grandchildren, which would presumably include Susan Foreman (TV: An Unearthly Child et.al.), though she indicates them to be missing, presumed dead. The Doctor previously indicated that he believed his family to be dead. (TV: The Tomb of the Cybermen, Gridlock)
 * She says the Doctor graduated with a doctorate in Glasgow in the wrong century. (TV: The Moonbase) She indicates this to be his only actual doctorate, although this is counter to what the Doctor and others have stated. (TV: The Armageddon Factor, Utopia, The God Complex)
 * He is from the constellation of Kasterborous. (TV: Pyramids of Mars, Voyage of the Damned)
 * He was a Prydonian. (TV: The Deadly Assassin) Clara indicates he lost this status when he stole the TARDIS. This is the first on-screen reference to this aspect of the Doctor's history in the modern era.
 * The Doctor previously claimed to have met Santa Claus, who he called "Jeff". (TV: A Christmas Carol)
 * When Missy states that the Doctor saved her, he says he saved Gallifrey and that it's lost. Missy responds that it's not lost, something that the Curator previously stated it was. (TV: The Day of the Doctor)
 * Missy states that Gallifrey has returned to its original place, with the coordinates of 10-0-11-00 by 02 (TV: Pyramids of Mars, Full Circle); however, it later appears that Missy lied.
 * Missy mentioned all the times she and the Doctor faced each other and the Doctor ask if she remember all the times she tried to dominate the world, before gleefully showing that thanks to her actions he's now President of Earth. (TV: Terror of the Autons et.al.)
 * Santa Claus knocks on the TARDIS' door three times with a rhythm of four, just like Wilfred Mott did when he fulfilled the prophecy, "He will knock four times." (TV: The End of Time)
 * Missy's Cybermen have a hive mind, like the Cyberiad on the Hedgewick's World of Wonders (TV: Nightmare in Silver).
 * In order to save her life, Clara tells the Cyberman she has important information and, alive, she is a tactical advantage. Rose Tyler used a similar argument to save her, Mickey Smith and Rajesh Singh from the Daleks (TV: Doomsday). Osgood later unsuccessfully tried to use this strategy to save herself from Missy.
 * Kate Stewart says the Doctor is on UNIT's payroll (TV: Spearhead from Space, The Day of the Doctor), but won't say how much he's being paid (if at all).
 * The Twelfth Doctor appears to have forgotten that he is employed by UNIT, despite the Eleventh making a point of this with Clara (TV: The Day of the Doctor).
 * At some point, St Paul's Cathedral was made bigger on the inside by Missy, who used it to store 91 Cybermen. (TV: Dark Water)
 * The Doctor continues to refer to Danny as "P.E." However, by the end of the episode, he says that he might yet make Maths teacher. (TV: The Caretaker et al) His final use of P.E. to refer to Danny is done with affection after he sees Danny post-conversion. Danny still chides the Doctor for acting like a "blood-soaked general" though.
 * The Doctor gives a reason as to why he doesn't like hugging, something to which he has been against in his current incarnation. (TV: Deep Breath, Listen)
 * The Doctor summons his TARDIS using a TARDIS key. (TV: Father's Day, The Time of the Doctor)
 * Missy tells the Doctor "Nice planet, this. Think I might keep it." She previously told the Half-Face Man she liked the Doctor's new accent and thought she might keep it. (TV: Deep Breath)
 * Missy suggests the Doctor to use the Cybermen army to free the people in the Dalek camps. (TV: The Dalek Invasion of Earth, Destiny of the Daleks, Asylum of the Daleks et.al.)
 * When the Doctor shows up to meet her two weeks late, Clara says he's improving, referring to his appearing three weeks late after being sent for coffee. (TV: Into the Dalek)
 * The Doctor has previously faced other enemies that weaponised the dead, including the Gelth (TV: The Unquiet Dead), the Daleks via nanocloud (TV: Asylum of the Daleks, The Time of the Doctor) and the Hoothi. (PROSE: Love and War)
 * The Cybermen utilise a modified form of rain that can transform organic matter into more of their kind. (COMIC: The Flood)
 * A Cyber-Leader also utilised a virus to turn the dead into Cybermen, but this was a ruse to trap the Sixth Doctor. (AUDIO: The Reaping)
 * While pondering Missy's offer of an army, the Doctor recalls several recent events since beginning his current incarnation:
 * asking Clara if he is indeed a "good man". (TV: Into the Dalek) He later says he is not a good man.
 * being offered a mocking salute by Danny Pink who also called him "Sir" (TV: The Caretaker) He later states that he is not an officer.
 * being told by Rusty that his soul contained hatred (TV: Into the Dalek)
 * telling Robin Hood he himself was not a hero (TV: Robot of Sherwood) He later says this to Missy.
 * also being told by Rusty that he was a "good Dalek" (TV: Into the Dalek).
 * The Doctor and Missy both refer to having been old friends. (TV: The Five Doctors, The Sound of Drums, The End of Time)
 * Missy says she has been up and down the Doctor's timeline and saw all the people who had died to save him. (TV: Deep Breath, Into the Dalek)
 * Missy makes a comment about "Loving the telly [on Earth]". (TV: The Sea Devils, The Sound of Drums)
 * Earth has previously endured a scenario in which people who are supposed to be dead continue to exist in some form. (TV: Miracle Day)
 * Referring to Missy, Clara angrily tells the Doctor "If you've ever let this creature live, then everything that happened today is on you". The Doctor once recalled how many people died because of his mercy. (TV: A Town Called Mercy)
 * Danny's reaction to his upgraded body is similar to the way the "Metaltron" Dalek responded when its biological form was modified against its will- in its case, the way the biomass it absorbed from Rose Tyler had altered its mind to the point it could have feelings. It lamented; "This is not life. This is sickness." Like Danny, it also self-destructed. (TV: Dalek)
 * It is shown in TV: the Magician's Apprentice that Missy survived her apparent death at the hands of the Brigadier. It is later explained in TV: The Witch's Familiar that Missy used the power of the Brigadier's blast to recharge her vortex manipulator and teleport away.
 * Like Missy, The Master has previously offered an immense wealth of power which he claimed he and The Doctor could use for good, only to reject it as no-one should have that sort of power (TV: Colony in Space).

DVD releases

 * Doctor Who: Series 8 Boxset

Blu-ray releases

 * Doctor Who: Series 8 Blu-ray Boxset

Digital releases

 * The episode was released on Google Play, iTunes and Amazon Instant Video in HD or SD, also available as part of the Series 8 digital boxset. The digital boxset contains various features: trailer, interviews, The Ultimate Companion, The Ultimate Time Lord, Inside the World Tour and Doctor Who Extra episodes for each episode.
 * In the US, the series was released through digital streaming services Hulu and Netflix with a subscription.