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 previous 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 its tank. However, it detects her, demanding she reveal 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, to which the Cyberman scans her again, and states she is indeed Clara Oswald. Clara insists that the Cyberman is wrong, and that the identity of "Clara Oswald" is just a story she made up. Clara states she is someone who would have to hide their identity from the Cybermen. With its interest piqued, the Cyberman demands she identifies herself. Clara then states she is the Doctor.

Outside of St Paul's Cathedral, the Doctor tries getting everyone to run away from the Cybermen, but everyone just ignores him. sarcastically passes him off as a ranting madman. The Doctor is baffled; 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; people take selfies with passive Cybermen. 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 dead Faction Cyberman in front of them; they left that behind on one of their previous attempts to conquer the Earth. The Cybermen use their rocket boots to escape.

The roof of St Paul's opens and more Cybermen fly out; Kate and the Doctor attempt to count them all, but fail. Osgood guesses eighty-seven due to her OCD, but 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 - the deceased will be returning to their bodies. 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 converts the deceased bodies 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 cooperation 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. The Doctor scoffs at the idea, but Kate reveals that the Doctor himself is the President.

Back in St Paul's, Clara uses her knowledge of the Doctor to convince the Cybermen that she is him. She even offers to reveal his true name, however, another Cyberman arrives and tells the others the truth about who she is. Clara tries to argue, saying that she is an incredible liar, to which the Cyberman agrees. The Cyberman then knocks her unconscious and kills the other Cybermen 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 in Boat One, the Doctor asks her how she is alive, and she states that he saved her when he saved Gallifrey. She then reveals that she knows where it is but refuses to tell him as seeing him in agony over not knowing is fun. 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. Impressed, the Doctor offers her a position in the TARDIS before he is called back to the office. 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 have come out yet, many more are hatching. Seeing Missy sticking her tongue out at him on the monitor, the Doctor realises 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. A pessimistic Doctor tells Colonel Ahmed to "throw away" his guns, as "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 and 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 speculates 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 "Mickey" replacing "Mickey" with "Missy". After drawing Osgood closer, she whispers a secret in her ear: "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 has 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. He takes the mask off his helmet, revealing his face to be severely mutilated by the cyber-conversion. Crying, he asks her to turn on his emotion inhibitor.

Meanwhile, back on Boat One, the Doctor realises that Missy had escaped her restraints and confronts her. Missy prompts him 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 needs to know that he is like her. The TARDIS phone begins ringing and Missy reveals that she both gave Clara the TARDIS' phone number and placed the advert in the Victorian newspaper. She claims that it was the only way to make sure the two of them — 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 to warn the Doctor 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. However, 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 TARDIS materialises in the graveyard and the Doctor warns Clara that if she deletes Danny's emotions, he will kill her. Danny denies this, and the Doctor says that the difference between himself and Missy is emotion; "pain is a gift". He tells Danny that "without the capacity for pain, we can't feel the hurt we inflict". 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 points out 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. Deciding that she needs to be the one to do it, 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 blank-faced. The Doctor asks him what Missy's plan for the Cyber Pollen is and he replies 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 onto the ground, 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 makes them demonstrate 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.

The Doctor refuses control of the army, but Missy points out that he 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 every time he wondered if he was a good man. He suddenly has a realisation and thanks Missy for helping him. He declares that 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 and 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 a 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, along with 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 from carrying the burden of a murder the rest of her life. 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.

Later, the Doctor meets Clara in a restaurant, the latter remarking that he is two weeks late, an apparent improvement compared to previous errors. The Doctor 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.

Thinking that he has found his way home at last, Clara changes her mind and goes along with the Doctor's belief that Danny has returned and that she too will be happy. Clara asks what he will do now; the Doctor 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 part ways with a hug. Clara asks why he doesn't like hugging and hethe Doctor responds that you should "never trust a hug" as "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.

Later, 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

Locations

 * Missy mentions New York, Paris, Rome, Marrakesh, Brisbane and Glasgow among the locations invaded by the Cybermen.
 * Danny's body was being stored at the Chaplet Funeral Home.

Technology

 * Missy's bracelet is able to give the mind of someone in the Nethersphere a physical body if they use it to teleport back to the real world, serving as a means of continual resurrection.

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 "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.
 * 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.
 * The Doctor is declared President of Earth following a UNIT protocol.

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.
 * 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 have a mid-credits scene.
 * 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.
 * Furthermore, in the same scene, as the disguised soldiers take selfies with the Cybermen and Missy pulls out her device to show the Doctor, the background of the scene changes from St Paul's to an entirely different street altogether.
 * 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

 * Kate tells the Doctor that her father always wanted a salute from him. The Tenth Doctor gave the Brigadier a sincere salute as a farewell after they saved Upper Wardleswick from Harpies. (COMIC: The Warkeeper's Crown)
 * While pondering Missy's offer of an army, the Doctor recalls asking Clara if he is a "good man", (TV: Into the Dalek) being offered a mocking salute by Danny Pink who called him "Sir", (TV: The Caretaker) 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) and also being told by Rusty that he was a "good Dalek". (TV: Into the Dalek)
 * Danny calling to Clara while she sleeps is very similar to the Tenth Doctor calling to Rose Tyler after she is trapped on a parallel Earth. (TV: Doomsday)
 * 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 Ninth Doctor encountered the same model of Cyberman headpiece as an exhibit in Henry van Statten's museum. (TV: Dalek)
 * Missy ordering the Cybermen in the graveyard mirrors how Mr Crane once ordered them likewise in the Cybus factory. (TV: Rise of the Cybermen) Miss Hartigan also gave Cybermen similar orders 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 Phelan, (AUDIO: Night of the Vashta Nerada) Lynda Moss, (TV: The Parting of the Ways) Madame de Pompadour, (TV: The Girl in the Fireplace) Astrid Peth, (TV: Voyage of the Damned) Jenny, (TV: The Doctor's Daughter) Rita, (TV: The God Complex) and Clara Oswin Oswald. (TV: The Snowmen)
 * Missy uses the phrase "Oh, my giddy aunt" when she is about to kill Osgood, a catchphrase frequently used by the Second Doctor. (TV: The Krotons, The Three Doctors, The Two Doctors)
 * 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 humorously 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)
 * 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)
 * 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)
 * 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)
 * 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)
 * 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)
 * 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)
 * 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)
 * 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)
 * 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) as well as John and Gillian, (COMIC: The Klepton Parasites) 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)
 * He is from the constellation of Kasterborous. (TV: Pyramids of Mars, Voyage of the Damned)
 * He was a Prydonian. (TV: The Deadly Assassin)
 * The Master has previously offered the Doctor a powerful weapon while also under the guise that it could be used for good, only for the Doctor to refuse, citing that no-one should have such power. (TV: Colony in Space) Lassar also offered the Tenth Doctor a powerful weapon, the Skasis Paradigm, but he also turned it down for similar reasons. (TV: School Reunion)
 * Kate reveals to the Doctor that he's on the UNIT payroll. Previously the Fourth Doctor said that he was UNIT's "unpaid scientific advisor". (TV: The Android Invasion)
 * The Twelfth Doctor stopping Clara from killing Missy on revenge mirrors certain events:
 * The third incarnation stopping Monia from killing the Controller for serving the Gold Dalek and its subordinates during the Time Paradox Incident. (TV: Day of the Daleks)
 * Rose Tyler stopping his ninth incarnation from murdering the Metaltron Dalek out of revenge. (TV: Dalek)
 * The tenth incarnation stopping Francine Jones from killing the Saxon Master for using her. (TV: Last of the Time Lords)
 * Amy Pond stopping the eleventh incarnation from giving Kahler-Jex to the Gunslinger. (TV: A Town Called Mercy)
 * Clara stopping the Ice Warrior Grand Marshal Skaldak from destroying Earth by reminding him of his daughter. (TV: Cold War)

DVD and Blu-ray releases

 * This story was released on DVD and Blu-ray as part of the Doctor Who: Series 8 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.