Doctor Who

Season 10

The Pilot

1. Several different sonic screwdrivers are shown sitting in a cup on the Doctor's desk, including models used by the Third, Fourth, and Eleventh Doctors.
2. The character of Bill was announced as the first openly gay character in the Doctor Who franchise. While this is true in the sense that she is attracted only to women, at least three of the Doctor's previous companions have expressed interest in multiple genders. Jack Harkness is best described as "pansexual", having had a number of lovers of various genders and species. Clara Oswald hinted at a relationship between herself and Jane Austen, and River Song (considered a companion in BBC lists) mentions seducing Cleopatra. In addition to this, the Doctor's allies Madame Vastra and Jenny are in a same-sex cross species marriage.
3. In the Doctor's office there are two busts. One of them is William Shakespeare and the other is Beethoven. Both are characters that the Doctor has met in his travels.
4. The "star" in Heather's eye is a real condition called central heterochromia, where a person's iris has a ring inside of it which is a different color than the outer edge of the iris. The star shape of Heather's ring, however, is uniquely hers.
5. Framed photos of River Song and Susan Foreman (The Doctor's wife and granddaughter, respectively) are shown on The Doctor's desk. River was last seen in Doctor Who: The Husbands of River Song (2015), which took place just before her death. Susan Foreman has not yet appeared in the new series (though some fans have speculated that the unnamed time lady featured in 'The End Of Time' might have been Susan; this has never been officially confirmed or denied).
6. The humanoids in white clothing with silver hair that the Doctor and Bill briefly encounter are Movellans, a race of androids. They fought the Daleks in the Tom Baker era episode Doctor Who: Destiny of the Daleks: Episode One (1979).
7. The sonic screwdriver that Matt Lucas uses during this episode is the Fourth Doctor's as in Tom Baker. Tom Baker was the narrator on Matt Lucas' hit British show Little Britian.
8. A wooden model raven in reference to his most recent companion Clara Oswald.
9. The vinyl record at the beginning of the episode in The Doctor's hand is RCA His Master's Voice UK B.D.1231 from Jan. 1949, a 10 inch 78 rpm record, Deck Of Cards by Phil Harris and T. Texas Tyler. The B side, which The Doctor kisses, is Pray For The Lights To Go Out by Phil Harris and Skidmore Tunnac.
10. Barring the gap between the classic series and the revival in 2005, this episode makes the longest break between Doctor Who series. The last regular episode (not a holiday special) aired 5 December, 2015.
11. Bill and Heather's romance may be an allusion to the first Doctor, William Hartnell. Hartnell often went by "Bill"; his wife's name was Heather.
12. Allusions are made between Bill and Rose Tyler. Bill works in the University canteen serving chips (fries); Rose once lamented that she would end up in a similar job, and actually did go undercover serving chips in a school. Bill's alarm clock has the exact same ring tone as Rose's; both are shown waking up to that alarm and going about their lives in a montage.
13. The other picture on the Doctor's desk, is that of Susan Foreman, his granddaughter (played by Carole Ann Ford). She was also the original companion.
14. The Doctor has several of his old Sonic Screwdrivers in a mug on his desk. Among them is the one used by the 10th Doctor, which must be a replica, due to the real one exploding in the 11th Doctor's first episode, The Eleventh Hour. Or it could simply be the one the Doctor gave to River Song, if he retrieved it after her death.
15. Jennifer Hennessy appeared in the Russell T. Davies' era of Doctor Who episode, Gridlock.
16. This episode was originally titled: A star in her eye.
17. When water is pouring down the stairs into the cellar, a sign saying "Mary Celeste" is visible in the corner. This is a reference to a First Doctor serial, The Chase, where The Doctor and his companions are trapped on the infamous ship after being chased by Daleks.
18. Filming started on June 20 of 2016 at Cardiff University.
19. Bill mentions that The Doctor was been lecturing at this university "...for over 50 years." Counting the old series, Doctor Who (2005) started over 50 years previously, and the episode that he left his granddaughter Susan, Doctor Who: Flashpoint (1964), aired over 50 years ago.
20. The Doctor is posing as a college professor. Ace, a companion of the Seventh Doctor, called the Doctor "Professor."
21. When they left Earth, the Doctor mentioned to Nardole that if there were any trouble with the vault, he'd get a message on his psychic paper. River Song previously sent him a request for help through the psychic paper in Doctor Who: Silence in the Library (2008).
22. Pearl Mackie, who plays the Doctor's newest companion Bill, makes her first appearance in this episode.
23. If you looks closely at the stained-glass window behind the Doctor when he is describing to Bill how he got the TARDIS in his office, you can see a name on clearly on one of the panes that says Robin Oxley and the letters "A" and "M". The way the stained-glass panel and candelabra are positioned spells out "Robin of Loxley" and the word "AIM". This could be a visual Easter-egg referring to Doctor Who: Robot of Sherwood (2014)
24. At the end of the episode, when The Doctor tries to wipe Bill's memories, she tearfully says, "just imagine how it would feel if someone did this to you." Clara's Theme plays after she speaks. Clara Oswald, The Doctor's previous Companion wiped his memories at the end of Doctor Who: Hell Bent (2015)
25. The plot point of a Time Lord hiding as a long-lived professor in a University on Earth was previously used in the incomplete Fourth Doctor serial "Shada", by Douglas Adams. Adams later incorporated elements of the story into his novel "Dirk Gently's Holisitic Detective Agency".
26. The alien puddle is seeking for a human being who wants to leave their current life situation, who will become its pilot. This plot device is similar to the Eleventh Doctor episode, "The Lodger", where an alien time ship also searches for a pilot among human beings who want to leave their present circumstances. Both entities use the phrase "Pilot has been found".

Smile

1. One of the pictures that Bill sees while she is reviewing the history of Earth on the spaceship is a self portrait of Vincent Van Gogh. It's the same portrait that Vincent offered the Eleventh Doctor as a parting gift during an earlier adventure, seen in the episode Doctor Who: Vincent and the Doctor (2010). This portrait is not a true replica of a real Van Gogh, but rather it's slightly altered to resemble Tony Curran, who played Van Gogh in that episode.
2. The tiny robots called Vardies are named after a professor at Memorial University in St. John's, Newfoundland, Canada. Andrew Vardy teaches computer science and electrical engineering, and his area of research is swarm robotics. Several years ago he worked with the episode's writer, Frank Cottrell Boyce, on a short story based on some of Vardy's ideas.
3. The spaceship's name is "Erehwon", which is almost the title of a novel by Samuel Butler, 'Erewhon', about a dysfunctional Utopia. It's also "Nowhere" spelled backwards.
4. The Doctor says "I'm happy, hope you're happy too." This is also a line from David Bowie's 'Ashes to Ashes'. Peter Capaldi is a big Bowie fan.
5. The Vardy city scenes were filmed at the City of Arts and Sciences in Valencia, Spain.
6. The teaser hints at the 1814 Frost Fair; which was the last one ever held in London. River once mentioned that the Doctor took her to this fair for her birthday in the episode "A Good Man Goes to War".
7. Mina Anwar also was a regular in the spin off series of The Sarah Jane Adventures (2007) as Rani Chandra (Anjli Mohindra)'s mum, Gita.
8. The Doctor tells Bill that if something chases you slowly, "it doesn't need to run." This is a call-back to the Doctor's experience with the slow-moving (but deadly) Veil in Doctor Who: Heaven Sent (2015)
9. The main reactor is a "Fleishman Cold Fusion Engine", and the name is also shown on the calorimeter gauge. This is a nod to the late Martin Fleischmann (name spelled differently) who was the British Chemist who claimed to have discovered cold fusion.
10. Ralf Little previously appeared in the computer game Doctor Who: The Adventure Games - The Gunpowder Plot (2011) as the voice of Guy Fawkes.
11. In February 1814, the Thames had frozen over and a "frost fair" was held on it. One of the draws was in fact an elephant being marched across the river beside Blackfriars Bridge.
12. The Doctor mentioned wondering where the "skeleton crew" was just before he found the bones of the colonists.

Thin Ice

1. The directions The Doctor gives Bill for the wardrobe are the same directions The Ninth Doctor gave Rose in "The Unquiet Dead" (2005).
2. The last Frost Fair was held in 1814. Dredging of the Thames to make new embankments and the new bridges increased the flow of the current, therefore the river could not freeze over as it used to.
3. The Doctor mentions having been to the Frost Fair "two times" before. In Doctor Who: A Good Man Goes to War (2011), River Song mentioned that the (Eleventh) Doctor took her (and Stevie Wonder) to this specific fair, the last one ever held in London, for her birthday. The other time may be the Big Finish Doctor Who story "Frostfire", narrated by Maureen O'Brien as Vicky Pallister, travelling with the First Doctor and Steven Taylor.
4. The men seen collecting money from people stepping onto the ice would have been the ferry men who lost their income when the river froze over.
5. The Doctor read "The Story of the Thumb-Sucker" to the urchins from "Shocking Peter" aka "der Struwwelpeter", a character from German folklore who punishes children for sucking their thumbs. Hoffmann's brilliant and twisted book of children's stories wasn't published until 1845, initially in German. Children in 1814 London, therefor, caught a glimpse of the future.
6. The young boy's name is "Peregrine", which means "wanderer" and is an appropriate name for a wandering street urchin.
7. In reality this Frost Fair came to an end as the ice melted and cracked suddenly. Two young gentlemen are said to have drowned as the traders and party goers scrambled to safety.
8. According to River Song in 'A Good Man Goes To War,' she and the (Eleventh) Doctor went to this Frost Fair to celebrate her birthday.
9. There really was a Frost Fair held on the frozen river Thames from 1st to 5th February, an elephant is reported to have been displayed on the ice.
10. When they first arrive in 1814 Bill is worried about slavery "still being totally a thing" and the Doctor agrees. Although slavery itself wasn't officially abolished in the British Empire until 1833, it essentially ended following the Slave Trade Act in 1807, before this episode was set. Slavery was also a feature of the British Empire and was never legal within the UK, something the Doctor would be well aware of.
11. The Doctor says that he is 2000 years old. He has previously stated this in 'Deep Breath'.
12. Lord Sutcliffe was born in 1783.
13. This episode takes place from February 4 to February 5, 1814 and in 2017.
14. The 1814 Frost Fair was the last of its kind as the mini ice age in Northern Europe came to an end after about 200 years.
15. The elephant in the very beginning is tooting the noise the TARDIS makes.
16. The Doctor states he's over 2000 years old. This seems to ignore the 4 Billion years he was trapped in the confession dial (Hell Bent / Heaven Sent).
17. The Doctor allowing Bill to decide the fate of the creature echoes a sentiment he previously expressed to Clara in Doctor Who: Kill the Moon (2014), that wherever possible it should be humans that decide what happens on their planet, not him.
18. As people flee the frozen river, Suttcliffe uses a plunger type detonator. Electrical detonators for black powder charges had been around since about 1750. The white disc clock facey part was a Wimshurst electrostatic generator, flanking it were two Leyden Jars that could store electrical charges. (The Wimshurst woulden't be invented for another 50 years)
19. Bill asks if anything she does in the past could have consequences in the future (the 'butterfly effect'). The Doctor tells her she just stepped on a butterfly, killing her friend Pete. In Doctor Who: Father's Day (2005), Rose Tyler saves her father's life, this having severe consequences for the future; his name was Pete.

Knock Knock

1. This episode used the same house as was previously used in Doctor Who: Blink (2007) and Doctor Who: The Snowmen (2012).
2. The Doctor asks the Landlord who the prime minister is and rattles off a list of names, including Harriet Jones, who was Prime Minister in the 'Doctor Who' universe.
3. Harry (Colin Ryan) was originally intended to be the grandson of Doctor Who (1963) companion Harry Sullivan (Ian Marter), but this was cut out because the writers thought that people "might not remember one companion from 40-odd years ago."
4. A special version was available on the BBC iPlayer immediately after the episode's broadcast. It contains a 3D sound mix, which requires headphones to give the viewer a more immersive sound experience.
5. The first name that the Doctor says to the Landlord (David Suchet) is Christie. This is a reference to Suchet's most famous role as Hercule Poirot in Poirot (1989) by Agatha Christie. Suchet and Peter Capaldi previously appeared together in an episode of that series, Poirot: Wasps' Nest (1991). Ironically, the Doctor and Donna met Agatha Christie in an episode called Doctor Who: The Unicorn and the Wasp (2008).
6. In one scene, the Doctor says to Bill "Up the wooden hill you go". In Britain, the phrase "Going up the wooden hill (to Bedfordshire)" is a form of saying "Going upstairs to bed". A "wooden hill" simply refers to the stairs.
7. The Doctor's observation that "sleep is for tortoises" is a reference to Doctor Who: The Talons of Weng-Chiang: Part Three (1977) in which the Fourth Doctor said the same thing.
8. Bill initally tries passing the Doctor off as a relative calling him "Granddad" but he says he prefers "Grandfather" both references to William Hartnell (The First Doctor), "Grandfather" is what Susan his first companion frequently refereed to him (the Doctor) as, whilst "Dad" was the nickname of the character that brought Hartnell to the attention of the original Producer Verity Lambert and was a large part in his subsequent casting in the Titular role, furthermore Bill is named after William Hartnell.
9. First time Bill directly states to be "into girls", as she puts it, whereas this far her preferences had only been hinted at (sometimes quite clearly) without directly stating.
10. The song the Doctor plays on Bill's phone is "Black Magic" by Little Mix. Since "Weird People" is also heard when Bill's friends arrive at the house, it could be implied that Bill is a Little Mix fan (Mixer).
11. Bart Suavek, who plays Pavel, also plays a character with the same name in two episodes of No Offence (2015).
12. Sam Benjamin has said that one of his influences when playing the Estate Agent was Ari Gold from Entourage (2004) played by Jeremy Piven.
13. All four episodes this season have plots that relate to missing or dying mothers. Doctor Who: The Pilot (2017) dealt with the Doctor getting Bill a photo of her mother. Doctor Who: Smile (2017) revolved around a boy looking for his (deceased) mother. Doctor Who: Thin Ice (2017) featured a gang of orphans. And the big reveal here was that the wooden lady was in fact the landlord's mother.

Oxygen

1. In an attempt to keep The Doctor on Earth, Nardole had removed the fluid link. In the first ever Dalek story, the First Doctor pretended the fluid link needed replenishing with mercury to enable the Tardis to take off and leave Skaro.
2. The Twelfth Doctor previously played with a yo-yo in "The Girl Who Died", co-written by Jamie Mathieson, who also wrote "Oxygen".
3. The opening line "Space. The Final Frontier" and the magnetic boots are nods to Star Trek (1966). "Space. The Final Frontier" is the famous line said by Captain James T. Kirk in the intro sequence and again in the feature films. In "Star Trek VI: The Undiscovered Country" (1991) and "Star Trek: First Contact" (1996) the Enterprise crew wear magnetic boots which stop them from floating away and allow them to walk on the exterior of the Enterprise in outer space.
4. Though not overtly stated, the electronic eyes on the suits resemble HAL 9000's eyes aboard Discovery and on the pods in 2001: A Space Odyssey (1968) They are also shown reading lips as HAL did.
5. This episode has the lowest UK overnight viewing rating than any other Doctor Who episode (3.57m).
6. When the Doctor offers to bring the survivors anywhere they want and tells them that the universe is their crustacean, he is paraphrasing "The world is Your Oyster", meaning "you can do what you want".
7. The Doctor previously gave Davros some of his regeneration energy in Doctor Who: The Witch's Familiar (2015) and said, "It might just cost me an arm or a leg someday, or I'll be really little." His inability to regain his sight here might be a side effect of that decision.
8. The classic science fiction horror film Alien (1979) may be an influence behind Doctor Who: Oxygen (2017). At the end of the story, The Doctor reveals that the corporation that built the space station are behind the deaths of the space station's crew due to the corporation's profit-making system and the deaths of the crew weren't due to a hack or malfunction. In Alien (1979), the film's main protagonist Ripley (Sigourney Weaver) discovers that the company that built the Nostromo space freighter have secretly ordered the ship's science officer Ash (Ian Holm) to return the alien to Earth and that the crew are expendable.
9. The first of a four part story that carry's on with "extremis", "pyramid at the end of the world" and "the lie of the land", although this entry is only loosely connected to the following three episodes, as it sets up the Doctor being rendered blind which plays an important role later.

Extremis

1. The sensor display in Doctor's sonic sunglasses give him a readout of nearby individuals' gender, age (presumably in years), height (in cm), weight (in lbs), heart rate (bpm) and temperature in degrees C. It is odd that it gives him weights in English units (pounds) and the others in Metric.
2. A repeating musical motif in this episode is the first and most recognizable 6 notes of the main theme from the James Bond film, "Thunderball (1965)", first heard at the beginning of "Dr. No" (1962).
3. The Doctor's "assumption" joke is a failed attempt to repeat an old joke about the word assume: "Never assume anything, because you make an ass out of u and me." (ass/u/me)
4. The portrait of Pope Benedict IX on the entrance to the Hereticum bears a striking resemblance to Angelina Jolie.
5. Joseph Long has previously appeared in Doctor Who in Series 4 Episode 11 "Turn Left".
6. The line that the scientist says to Bill and Nardole, "We'll all go together when we go," is from the Tom Lehrer song of the same name.
7. Among the email subject lines in the priest's laptop are: 'The world is not what we think it is', 'The devil's work has been done', 'We have been tricked', and 'Please follow suit.'
8. The Doctor is left blind from the events of the last episode "Oxygen".

The Pyramid at the End of the World

1. The real Doomsday Clock is maintained by the members of The Bulletin of the Atomic Scientists' Science and Security Board. As of May 2017, the actual setting is 2.5 minutes to midnight.
2. The Doctor's sonic sunglasses show that Bill is a 26 year old female who weighs 130.2 pounds, is 167.6 cm tall, has a heart rate of 79 bpm and a body temperature of 37.6 degrees C.
3. Doomsday Clock update: As of January 2020, it is set at 100 seconds (1 minute 40 seconds) before midnight; which is the closest to midnight the clock has ever been set since it's foundation in 1947. In the immortal words of P.F. Sloan, "We're on the eve of destruction."
4. "Enzyme EC 31" tank seen in the lab is probably based on the real Enzyme Comission (EC) number system for classifying enzymes based on the chemical reactions they catalyze. However the real codes are in the form of four numbers separated by periods.
5. The theme of the 10th Doctor can be heard in several scenes.
6. The bomber aircraft is a Boeing B-52 Stratofortress.

The Lie of the Land

1. A scene shows people standing outside a TV shop named Magpie Electrical. This is the name of the television shop used in Doctor Who: The Idiot's Lantern (2006) with the 10th Doctor and Rose.
2. Under the monks everyone wears blue overalls, just as they do in Orwell's 1984.
3. The Ministry of Truth van and the aliens' pyramid in the middle of London are references to Orwell's 1984, where the ministries were huge, pyramid-shaped buildings.
4. Magpie Electrical is also seen in Season 5 Episode 2, The Beast Below. Amy passes by it when she enters the tent covering the opening to the lower workings of Starship UK.
5. This episode is the third part of a three-part story (Extremis, The Pyramid at the End of the World, The Lie of the Land).
6. at 24:10, Missy refers to Nardol as "that bald bloke...that looks like an egg" Matt Lucas portrayed Tweedledee/Tweedledum in the live action adaptations of Alice in Wonderland--characters that look very egg-like.
7. When Nardole pinches and thereby incapacitates Alan, he says he did it by using "the Tarovian neck pinch". This bears a striking resemblance and is most likely a nod to Spock's Vulcan Nerve Pinch in the original Star Trek series, another series about traveling in space (and what sometimes resembles time) meeting different aliens.

Empress of Mars

1. The picture of Queen Victoria is a picture of the actress Pauline Collins, in character, from when she appeared in the 2nd series episode, "Tooth and Claw".
2. At one point the Doctor gives a poetic account of the Ice Warriors and Bill replies "...like the Vikings." In the original script for the Ice Warriors' first appearance in 1967, they were intended to be futuristic Vikings with bionic armor before being changed to reptiles.
3. This marks the first appearance of a female Ice Warrior.
4. 'Empress of Mars' is the ninth episode of "Doctor Who" (2005) that is written by Mark Gatiss. At the time of its first airing, Mark Gatiss became the longest serving writer of Doctor Who since the revival, his first contribution being the third episode of Series 1, 'The Unquiet Dead'.
5. Friday tells Irraxa that they have slept for 5000 years. Presumably he meant 5000 Mars years, which would equal about 9500 Earth years.
6. This episode takes place in 2017 and 1881.
7. Anthony Calf (Colonel Godsacre) previously played Charles in Doctor Who: The Visitation: Part One (1982).
8. The enlisted men are wearing the number "24" on their shoulders. This is most likely their regiment. The 1st battalion 24th Foot was wiped out at Islandlwana on January 22, 1879. A company from the same regiment was victorious that same day at Roarke's Drift winning 11 Victoria Crosses - Britain's highest military honor.
9. Ysanne Churchman, who was the original voice of Alpha Centauri in the third Doctor stories 'The Monster of..' and 'The Curse of Peladon', returned as the voice of Alpha Centuri in this episode, even though she was 25 years into retirement at the age of 92.
10. This episode acts as a prequel to "The Curse of Peladon" (1972) and "The Monster of Peladon" (1974), in that it ends with the Ice Warriors forming an alliance with the Galactic Federation, who are shown working alongside them in the '70s stories.
11. Ysanne Churchman's return as Alpha Centauri marks only the fifth time a "Doctor Who" (1963) character has come back in "Doctor Who" (2005), played by the same person. The other four instances have been Sarah Jane Smith by Elisabeth Sladen, K-9's voice by John Leeson, the Fifth Doctor by Peter Davison in the Children in Need Special, "Time Crash" (2007) and the Eighth Doctor by Paul McGann in the online prequel, "The Night of the Doctor" (2013).
12. Doctor Who: Empress of Mars (2017) is a prequel to Doctor Who: The Curse of Peladon: Part One (1972) which featured The Ice Warriors and Alpha Centauri.
13. This episode marks the return of Alpha Centauri.
14. This marks only the second time in Doctor Who (2005) since its revival that we have seen the Ice Warriors of Mars. They were shown several times during the 2nd Doctor's (Patrick Troughton) run and a few times during the 3rd Doctor's (Jon Pertwee) in the follow up to this story The Curse of Peladon , and The Monster of Peladon, both of those stories also involved the character of Alpha Centauri, voiced by the same actress.
15. When finding the tomb of the Ice Queen, the Doctor utters a phrase made famous by the Star Wars Saga: "I have a bad feeling about this."

The Eaters of Light

1. When Kar says of the Romans "...their work is robbery, slaughter, plunder. They do this work and they call it 'empire'. They make deserts and they call it 'peace'", it is a direct reference to the famous speech made by the (probably fictional) Celtic general Calgacus, from the Roman book Tacitus.
2. Acclaimed Scottish playwright Rona Munro had previously been commissioned by script editor Andrew Cartmel to write the final transmitted serial of the original series, Doctor Who: Survival: Part One (1989). She becomes the first person to have been accepted to write for both Doctor Who (1963) and Doctor Who (2005).
3. The Doctor angrily tells Kar that she, "got the deadliest creature on this planet very cross". Although the implication is that he's referring to the Eater of Light, he could just as easily be referring to himself.

World Enough and Time

1. The title is taken from Andrew Marvell's poem 'To His Coy Mistress', written c1650 and only published posthumously in 1681.
2. The Doctor uses Venusian Akido on Jorj. This is a discipline that the third doctor used extensively, and was used previously by the twelfth doctor in Doctor Who: Robot of Sherwood (2014)
3. Missy mentions that the Doctor's real name is "Doctor Who" and eventually he just shortened it to "The Doctor". For all of Doctor Who (1963) and up to Doctor Who: The Parting of the Ways (2005) in the new series, the lead character was listed in the credits as "Doctor Who". Subsequently this became just "The Doctor".
4. Razor's room is reminiscent of the BBC's Radiophonic Workshop of the 1960s, at least as recreated in Cardiff's 'The Doctor Who Experience', where the groundbreaking and iconic electronic theme music was created.
5. Missy's introduction of her companions is reminiscent of The Cat in the Hat (1971) where the title character has an umbrella, and his traveling companions are "Thing One" and "Thing Two".
6. Power Rangers Wild Force: Reinforcements from the Future: Part 2 (2002) is speculated to be a possible influence behind (#10.11).
7. This is the first time in the series where different incarnations of The Master appear together.
8. This is the first appearance of the original Cybermen since "The Tenth Planet" which aired 53 years before.
9. Although the Master's return was obviously meant to be a surprise, the BBC announced it ahead of time in order to prevent leaks in the press. John Simm openly expressed his displeasure on the subject, as he felt most viewers were able to see through the Master's disguise before the big reveal at the end of the episode.
10. John Simm has facial hair in this two-part finale like his previous incarnations, Roger Delgado (1971-73) and Anthony Ainley (1981-89). Also this is his second time he uses his laser screwdriver which was last seen in "Last of the Time Lords" a decade ago in 2007.
11. Prequel to Doctor Who: The Tenth Planet: Part One (1966) (TV Episode).
12. (#10.11) reveals the Mondasian Cybermen were created by The Master.
13. Bill's tear as a relunctant Cyberman recalls a similar tear shed by Yvonne Hartman (Tracy Ann Oberman) in "Doomsday," the finale of season 2. Hartman works for Torchwood and though converted into Cyberman, she turns on them and mows them down, shedding an oily "tear." In the episode after this one, the season 10 finale, when the Doctor wipes away one of Bill's tears, she asks if it is engine oil.
14. The Master's speech describes a 'Genesis of the Cybermen', this is a reference to the 4th Doctor (Tom Baker) story, 'Genesis of the Daleks', an origin story of the Daleks which has been widely appraised as one of the greatest classic Doctor Who episodes of all time.
15. Though the Doctor never called himself Doctor Who before this, the credits at the end of every episode of the original series through 1981, listed the part as Dr. Who, followed by the current lead actor's name.
16. Having The Master (John Simm) in heavy disguise (but not convincing) for most of the episode, with a reveal at the end is reminiscent of classic Doctor Who, where The Master played by Anthony Ainley would be disguised for most of an episode - often pretending to be a helpful and friendly character.
17. In this episode, Peter Capaldi becomes the first and only Doctor, so far (in canonical stories) to refer to himself as Doctor Who.
18. This is the 2nd time (or 3rd episode if the 2-parter; The Impossible Planet and The Satan Pit are counted as one), in which the Doctor is aboard a ship in geostationary orbit around a black hole.
19. This marks the first time in either this series or the original launch in which The Doctor introduces himself as "Doctor Who." Although the title character in Dr. Who and the Daleks (1965) and Daleks' Invasion Earth 2150 A.D. (1966), played by Peter Cushing, identifies himself by that name, those films are not considered canonical within this show. Other characters in the original series referred to him as such, but The Doctor himself has consistently referred to himself as "The Doctor" throughout.
20. The Master makes a comment "is the future going to be all female?" Possible foretelling that the Doctor is about to regenerate into a female as well
21. The tear in the eye of Bill as a Cyberman reminiscent of Picard / Locutus of Borg in similar circumstances in episode 1 series 4 of Star Trek, The Next Generation. Humanity trying to overcome integration into a robotic state of being.

The Doctor Falls

1. In an interview given to the Radio Times, Steven Moffat said that he and his predecessor Russell T. Davies briefly considered pranking incoming showrunner Chris Chibnall by telling him (falsely) that this story would end with Missy being pregnant.
2. While talking to Bill in the barn, The Doctor offers a little girl Jelly Babies, which were a favorite of the fourth incarnation of The Doctor.
3. The Master asking if the future was going to be "all girl", and the 12th Doctor's response of "We can only hope." references the fan speculation regarding whether or not the 13th Doctor would be female. Jodie Whittaker was announced as the 13th Doctor a few weeks after this episode aired.
4. The line "I'm the Doctor... the original, you might say." is spoken by both incarnations of the Doctor and is equally valid in both cases, as in the series, the word "Doctor" was revealed in the episode "A Good Man Goes to War" as having originated from the Doctor himself.
5. The Cybermen have appeared in the twelfth episode of a every series since series 5.
6. The names of the members of the Hartnell family that appeared in the anniversary special "An Adventure in Space and Time" appeared throughout the first season. Bill Potts connects to William Hartnell, (The First Doctor) who was called Bill by his friends. Heather, Bill's girlfriend with the star-shaped iris, has the same name as William Hartnell's wife, Heather. The little girl investigating the standing stones at the beginning of "Eaters of Light" was named Judy, like Judith Carney, Hartnell's granddaughter. However, according to Steven Moffat, this was simply a coincidence.
7. The plaid coat worn by Matt Lucas, is the same coat worn by Bob Hoskins in the film Outside Bet (2012). The Coat was provided to both productions by costume designer Hayley Nebauer. The coat is now in the hands of a Private Collector.
8. Multiple times throughout the episode when The Doctor talks to Cyberman Bill he looks down at her like his talking to shorter human Bill and not taller Cyberman Bill.
9. The First Doctor's clothing and the arctic setting are both consistent with "The Tenth Planet", the final serial to feature the First Doctor. William Hartnell was absent from the filming of that serial for several days due to his progressive illness, which required rewrites to cover the absence of the First Doctor from the story. This has led to speculation that the encounter between the First and Twelfth Doctors takes place during the events of "The Tenth Planet", during the time when the First Doctor was absent from the main adventure.
10. This is the second time the Doctor has tried to suppress his regeneration. Previously, the Tenth Doctor suppressed his regeneration long enough to look in on every one of his former companions. According to a line from The Sarah Jane Adventures (2007)" he looked in on every companion from the original and modern series up to that point. Prior to that in the series, the Tenth Doctor was also able to successfully suppress a regeneration by siphoning off energy to his severed hand, thereby retaining his appearance after healing himself.
11. Bill's final fate is very similar to that of Clara, the Doctor's previous companion. Both are exploring the universe on their own in the company of another woman. Both have been rescued from what appeared to be an inevitable death, and in both cases, the Doctor is left unaware of their survival.
12. When the Master and Missy are tormenting the Doctor about possible ways of killing him, they mention that they know he died once by falling. The Fourth Doctor's regeneration was triggered when the Master caused him to fall from a Radio telescope.
13. Both the 12th and 1st Doctors say "I'm the Doctor... the original, you might say.", referencing a line spoken by the First Doctor in the 20th anniversary episode "The Five Doctors". Ironically, the line was spoken by Richard Hurndall, who replaced William Hartnell as the First Doctor after the latter's demise.
14. The Cybermen first appeared in "The Tenth Planet", which was the episode that featured the First Doctor's regeneration. The First Doctor wears the same outfit he wore in "The Tenth Planet'.
15. The Master was stranded due to a broken dematerialization circuit. This was the same component that the Time Lords deactivated in order to disable the Third Doctor's TARDIS and exile him to Earth. It was during this period of exile that the character of the Master was first introduced.
16. As the Doctor destroys the Cybermen he recites places where he defeated them previously. One of those sites (Marinus) does not refer to a defeat in televised adventures but in a 1987 Dr. Who comic strip.
17. Features 3 generations of Cybermen: The original Mondasian variant, 2006 Cybus variant and the 2013 redesigned variant
18. As the Doctor is suppressing his regeneration, he flashes back on memories of his former companions and allies, which had also happened when the Fourth and Fifth Doctors regenerated. The last person he sees is Missy/The Master, who also appeared as a vision during the Fifth Doctor's regeneration. He also repeats the the last words of the Tenth Doctor, "I don't want to go", and the Eleventh Doctor, "(I will always remember) when the Doctor was me."
19. Aside from "one-off" companions that appeared in Christmas specials and single episodes, the companions of the modern era that are not shown during the Doctor's vision are two of his male companions: Mickey Smith and Rory Williams.
20. Similar to the Doctor at the end of this episode, the John Simm version of the Master refused to regenerate at the end of "The Last of the Time Lords", which resulted in his death from a gunshot wound.
21. The first appearance of David Bradley in the role of the First Doctor, originated by William Hartnell. Bradly previously played William Hartnell and reenacted scenes from Hartnell's tenure as the First Doctor in the BBC film "An Adventure in Space and Time".
22. Missy tells the Master "I loved being you" and speaks of her admiration of him, echoing the Tenth Doctor's speech to the Fifth Doctor in the Doctor Who mini-episode "Time Crash".
23. As of this episode, Steven Moffat has written original material for eight different incarnations of the Doctor: the First, Fifth, Eighth, Ninth, Tenth, Eleventh and Twelfth, plus the War Doctor.
24. Reveals John Simm's Master's reason for regeneration into Missy. As well as the (presumed) death of Michelle Gomez's Missy
25. The final appearance of Peter Capaldi as the Doctor in regular episodes. His final appearance in the role is in the 2017 Christmas Special.
26. David Bradley played William Hartnell (the First Doctor) in the BBC film An Adventure in Space and Time (2013). David Bradley plays the First Doctor for real in this episode.
27. The Master (while still in disguise) previously told Missy that neither she nor he would do anything "self-destructive" like harming each other. This turned out not to be true.
28. Disregarding Time Crash and archive footage, this is the first time a classic Doctor appears in Doctor Who and interacts with the current Doctor (Peter Capaldi). Unless of course you count Tom Baker in Day of the Doctor.
29. Fans had assumed that (#10.12) was indeed Pearl Mackie's last episode as Bill Potts. Pearl Mackie did return for the 2017 Christmas Special which she played Bill Potts one last time.
30. Final appearance of Michelle Gomez as Missy. Although Missy dies from her shot wound when she was shot with her previous incarnation's laser screwdriver, there's a possibility Missy could return in a future season as Missy is a Time Lady and can Regenerate and Missy could return in another female form or as a male which she would change from Missy back to The Master.