<P> Steven Moffat wrote four episodes for the series . Other returning writers who have worked on this series and previous ones include Frank Cottrell - Boyce, Sarah Dollard, Jamie Mathieson, Peter Harness, Toby Whithouse and Mark Gatiss, as well as two new writers for the revived era of the programme, Mike Bartlett and Rona Munro, the latter of whom wrote Survival, the final serial of the original classic era . Directors of the series included three who have previously worked on the show, and three brand new ones . Filming began on 20 June 2016 and lasted just over nine months, ending on 7 April 2017 . The series received positive reviews from critics . The performances of Capaldi and Mackie were met with the most praise, as well as the writing, plots and themes of the episodes . </P> <P> The sixth, seventh and eighth episodes of the series, "Extremis", "The Pyramid at the End of the World", and "The Lie of the Land", constitute a three - part arc while remaining separate stories . The episodes "World Enough and Time" and "The Doctor Falls" serve as the series' two - part finale and only multi-part story, in the same format as the eighth series . </P> <Table> <Tr> <Th> Story </Th> <Th> Episode </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> UK viewers (millions) </Th> <Th> AI </Th> </Tr> <Tr> <Td_colspan="13"> Special (2016) </Td> </Tr> <Tr> <Th> 264 </Th> <Td>--</Td> <Td> "The Return of Doctor Mysterio" </Td> <Td> Ed Bazalgette </Td> <Td> Steven Moffat </Td> <Td> 25 December 2016 (2016 - 12 - 25) </Td> <Td> 7.83 </Td> <Td> 82 </Td> </Tr> <Tr> <Td_colspan="8"> The Doctor and Nardole investigate the New York branch of "Harmony Shoal", a multinational research company . Also investigating is journalist Lucy Fletcher, and they discover that Harmony Shoal is transplanting alien brains into humans . One of the alien workers finds the three, but they are rescued by the superhero called the Ghost, an alter ego for Grant Gordon, whom the Doctor met several years before when Grant was a child and accidentally turned him into a superhero . Grant is also a nanny working for Lucy, who is unaware of Grant's true identity . The Doctor and Nardole find the aliens' ship, but soon discover that it has been turned into a bomb that will crash into New York as part of a complex plan to implant the alien brains into world leaders, thereby giving them control of the Earth . The Doctor aims the ship towards New York earlier than planned and the collision is stopped by Grant, revealing his identity to Lucy . After he and Lucy announce their love for each other, Grant throws the ship into the sun . UNIT then shuts down Harmony Shoal, but an alien brains implants itself into a UNIT soldier . </Td> </Tr> <Tr> <Td_colspan="13"> Series </Td> </Tr> <Tr> <Th> 265 </Th> <Td> </Td> <Td> "The Pilot" </Td> <Td> Lawrence Gough </Td> <Td> Steven Moffat </Td> <Td> 15 April 2017 (2017 - 04 - 15) </Td> <Td> 6.68 </Td> <Td> 83 </Td> </Tr> <Tr> <Td_colspan="8"> The Doctor and Nardole have occupied themselves under the guise of a university professor and assistant . Bill Potts is called to the Doctor's office, where she becomes the Doctor's student . Bill is intrigued by a student named Heather . Heather asks her to inspect a puddle, asking her if she can see what's wrong with her reflection . The Doctor investigates the puddle, and notes that it is not a reflection, but something mimicking them . Bill returns to her flat, where she is chased by a moving body of fluid: a living fluid from an alien ship that has absorbed Heather and her feelings for Bill . Bill runs to the Doctor's office and they flee into the TARDIS . The Doctor moves the TARDIS, where he and Nardole check on a vault they are guarding . The TARDIS lands again in Australia, where the Doctor admits who he is . The fluid follows them to another planet in the future, then through a Dalek battle, but survives . Bill convinces "Heather" to let her go, and it departs . The Doctor and Bill return to his office, where he attempts to wipe Bill's memories of the day but she stops him . As Bill leaves, she finds the Doctor waiting with the TARDIS, and joins him . </Td> </Tr> <Tr> <Th> 266 </Th> <Td> </Td> <Td> "Smile" </Td> <Td> Lawrence Gough </Td> <Td> Frank Cottrell - Boyce </Td> <Td> 22 April 2017 (2017 - 04 - 22) </Td> <Td> 5.98 </Td> <Td> 83 </Td> </Tr> <Tr> <Td_colspan="8"> The Doctor and Bill arrive on one of Earth's first colonised planets, Gliese 581d . They are greeted only by two different types of robots: swarm robots (Vardies) and slow but sentient emojibots . An emojibot gives the Doctor and Bill discs that communicate their true emotions . The Doctor theorizes that the planet is awaiting the colonists but soon realizes that the setup crew has been killed by emojibots and their skeletons crushed to feed the plants . Determined to blow up the city, he finds the main ship within it and its engine room, but Bill runs into a child who has awoken from a pod . The colonists were cryogenically frozen, with a few "shepherds" woken early to work . After one shepherd died, the emojibots could not recognise grief and killed all in mourning in an onslaught against sadness . The awakened colonists decide to fight back, but the Doctor wipes the memory of the robots and reboots everything...only humans must now learn to live with the Vardies, the planet's indigenous species . When the TARDIS returns the Doctor and Bill to London, they discover themselves on a frozen Thames River, with an elephant walking towards them on the ice . </Td> </Tr> <Tr> <Th> 267 </Th> <Td> </Td> <Td> "Thin Ice" </Td> <Td> Bill Anderson </Td> <Td> Sarah Dollard </Td> <Td> 29 April 2017 (2017 - 04 - 29) </Td> <Td> 5.61 </Td> <Td> 84 </Td> </Tr> <Tr> <Td_colspan="8"> The Doctor and Bill find they have arrived in 1814 London, in the midst of a frost fair on the frozen Thames . The Doctor's sonic screwdriver is stolen by Spider, an orphan pickpocket led by Kitty . The Doctor and Bill chase after Spider and Kitty . Glowing lights under the ice encircle Spider's feet and he is pulled through the ice . The Doctor and Bill don diving suits and purposely let the lights take them; they find a giant sea creature ensnared by chains . They learn from Kitty of Lord Sutcliffe; Sutcliffe affirms his family has used the creature to amass a fortune by collecting and selling its waste as a replacement for coal . Sutcliffe sends the Doctor and Bill to be eaten, while he rigs a bomb to cause the ice to shatter . The Doctor and Bill escape, and the Doctor takes the bomb and places it on the creature's chains . When Sutcliffe sets off the bomb, the creature is freed . They return to the present, where Nardole scolds the Doctor for breaking his oath . While checking the Vault beneath the University, Nardole hears something behind it knock repeatedly . </Td> </Tr> <Tr> <Th> 268 </Th> <Td> </Td> <Td> "Knock Knock" </Td> <Td> Bill Anderson </Td> <Td> Mike Bartlett </Td> <Td> 6 May 2017 (2017 - 05 - 06) </Td> <Td> 5.73 </Td> <Td> 83 </Td> </Tr> <Tr> <Td_colspan="8"> Bill and five students sign a lease with a mysterious Landlord to live in his manor house . After helping Bill move in, the Doctor becomes suspicious of the Landlord . A number of the students mysteriously disappear and the groups are separated . The Doctor along with Harry, one of the students, discover a strange cockroach - like creature which the former nicknames "Dryads". Down in the basement they discover leases from decades ago . The Landlord reveals the whole incident was to keep his daughter, Eliza, alive . Bill and another student, Shireen, come across Eliza who is revealed to composed of wood . After finding Bill, the Doctor realises that the Landlord is actually Eliza's son . The Landlord attempts to send the Dryads after the Doctor and Bill, but Eliza manages to control them . She embraces the Landlord as the Dryads consume them . The students are restored to their physical bodies as the house collapses . Back at the university, the Doctor enters the vault to feed their prisoner as piano music echoes from inside . </Td> </Tr> <Tr> <Th> 269 </Th> <Td> 5 </Td> <Td> "Oxygen" </Td> <Td> Charles Palmer </Td> <Td> Jamie Mathieson </Td> <Td> 13 May 2017 (2017 - 05 - 13) </Td> <Td> 5.27 </Td> <Td> 83 </Td> </Tr> <Tr> <Td_colspan="8"> Nardole accompanies the Doctor and Bill to a space station to answer a distress call . Most of the crew have been killed by their smartsuits, robotic spacesuits capable of independent movement which are the only source of oxygen on the station, forcing the TARDIS crew to don spares . The suits received an order to "deactivate organic components"; some crew survived by being disconnected, but networked suits can transmit the command by touch . Bill's suit malfunctions, forcing the Doctor to give her his helmet to save her, exposing himself to the vacuum of space, which blinds him; he later leaves her behind to be electrocuted, knowing her suit hasn't the power for a lethal shock . The algorithm used by the company determined the crew were inefficient and thus too expensive to keep alive . He wires the survivors' life signs to the station so that if they die it will explode, making it more expensive to kill them, so the suits give over their remaining oxygen . Bill is revived, the Doctor's eyes are repaired, and the survivors return to their head office to complain . Back at the university, the Doctor reveals to Nardole he is still blind . </Td> </Tr> <Tr> <Th> 270 </Th> <Td> 6 </Td> <Td> "Extremis" </Td> <Td> Daniel Nettheim </Td> <Td> Steven Moffat </Td> <Td> 20 May 2017 (2017 - 05 - 20) </Td> <Td> 5.53 </Td> <Td> 82 </Td> </Tr> <Tr> <Td_colspan="8"> A long time ago, the Doctor is sent to execute Missy, only to have Nardole interrupt on the behest of River Song . The Doctor refuses to kill Missy, instead opting to imprison and guard her for 1000 years . In the present, the Pope comes to the Doctor, asking to help translate a text called "Veritas". Everyone who has read it has committed suicide, and the Doctor, Nardole, and Bill are brought to the Vatican to investigate . While there, Bill and Nardole discover a portal which leads them to the Pentagon . They find the portals being projected lead to different locations all over the world . The Doctor temporarily restores his sight using Time Lord technology, but is ambushed by aliens . Nardole realizes the projectors are not projecting portals, but the whole world . His realization causes him to dematerialize . Bill finds the Doctor, who tells her the world is a simulation, and Veritas contains the proof . Bill then disappears due to the alien's intervention, the Doctor realizing this is a test to see if they can conquer the Earth . However, the simulation is too exact, as his sonic sunglasses still work perfectly, and the virtual Doctor sends his information to the real Doctor warning of the coming invasion . </Td> </Tr> <Tr> <Th> 271 </Th> <Td> 7 </Td> <Td> "The Pyramid at the End of the World" </Td> <Td> Daniel Nettheim </Td> <Td> Peter Harness and Steven Moffat </Td> <Td> 27 May 2017 (2017 - 05 - 27) </Td> <Td> 5.79 </Td> <Td> 82 </Td> </Tr> <Tr> <Td_colspan="8"> The Doctor is called in by the Secretary - General of the U.N. after a pyramid mysteriously appears on the strategic border of the Russian, Chinese and U.S. armies . It is revealed the Monks are responsible for the pyramid and that they have forseen a disaster through their simulations, offering an opportunity to save humanity if they consent to their rule . Elsewhere in a biochemical lab, a scientist accidentally misreads the levels of chemicals in an experiment releasing deadly biochemical bacteria . The Secretary - General offers his consent, but is killed when he is viewed to be acting out of fear . The Doctor surmises that the disaster was unrelated to war, but may be biochemical . After the Doctor and Nardole locate the lab, Nardole collapses following exposure to the bacteria whilst waiting in the TARDIS . The Doctor with the assistance of Erica, a lab worker, surmises the only way to stop it would be to destroy the lab . He becomes stuck on the side of a manual lock however, due to his blindness . Bill makes a deal with the Monks to restore the Doctor's sight despite his protests . He manages to escape but at the expense of handing the planet over to the Monks . </Td> </Tr> <Tr> <Th> 272 </Th> <Td> 8 </Td> <Td> "The Lie of the Land" </Td> <Td> Wayne Yip </Td> <Td> Toby Whithouse </Td> <Td> 3 June 2017 (2017 - 06 - 03) </Td> <Td> 4.82 </Td> <Td> 82 </Td> </Tr> <Tr> <Td_colspan="8"> The Monks now rule the planet, and to most of humanity, they appear to have been on Earth for millions of years, guiding human development . Bill and a few others know the truth . Nardole locates Bill, and they search for the Doctor . They locate him, but he is cooperating with the Monks . Bill shoots him and it appears he is regenerating, but it is all a trick to see whether Bill has been fooled by the Monks . At the university, the Doctor speaks to Missy, who reveals Bill has to die to break the Monk's influence on Earth . The Doctor hopes there is another solution, and infiltrates the Monk's pyramid in London . The Doctor attempts to break the link but fails . Bill prepares to sacrifice herself, however the Monk's images are replaced with those of Bill's mother, which represents hope . Due to their actions, the Monks leave and humanity recall none of the events . Back in the Vault, Missy expresses remorse at those she has murdered . </Td> </Tr> <Tr> <Th> 273 </Th> <Td> 9 </Td> <Td> "Empress of Mars" </Td> <Td> Wayne Yip </Td> <Td> Mark Gatiss </Td> <Td> 10 June 2017 (2017 - 06 - 10) </Td> <Td> 5.02 </Td> <Td> 83 </Td> </Tr> <Tr> <Td_colspan="8"> NASA finds the words "God save the Queen" buried under the ice cap of Mars . The Doctor, Bill and Nardole venture to Mars in 1881 and discover soldiers from Victorian Britain . Nardole goes back into the TARDIS, but it returns to the university, and he asks Missy for help getting back . The humans have befriended an Ice Warrior named Friday . Captain Catchlove says they rescued Friday from his crashed spaceship, and Friday allowed the soldiers to use his technology to mine Mars . They unearth the tomb of the Ice Empress Iraxxa; one guard revives her . Friday tells Iraxxa that the Martian surface is uninhabitable . She decides to relent, but a soldier fires his rifle; provoked, she returns fire . Iraxxa starts reviving Ice Warriors . The Doctor threatens to use the mining device to bury them all . Catchlove holds Iraxxa at knifepoint and attempts to force her to help him pilot a spaceship . Godsacre kills Catchlove . Iraxxa calls off the attack in exchange for Godsacre pledging himself to her . The Doctor contacts Alpha Centauri to assist the Ice Warriors, and also leaves the message for NASA . Nardole re-appears with the TARDIS and Missy, who expresses concern about the Doctor . </Td> </Tr> <Tr> <Th> 274 </Th> <Td> 10 </Td> <Td> "The Eaters of Light" </Td> <Td> Charles Palmer </Td> <Td> Rona Munro </Td> <Td> 17 June 2017 (2017 - 06 - 17) </Td> <Td> 4.73 </Td> <Td> 81 </Td> </Tr> <Tr> <Td_colspan="8"> The Doctor and Bill, disagreeing about the fate of the Ninth Legion of the Imperial Roman army, travel in the TARDIS to the 2nd century in Scotland . Bill goes her own way, while the Doctor and Nardole look for their bodies . Bill encounters the Legion's soldiers hiding from a creature drawn to any light source, killing those in its path . Meanwhile, the Doctor and Nardole discover the corpses of the remaining Legion . They later come across a Pict tribe guarding a cairn . The Doctor enters the cairn, passing into an interdimensional portal . The Pict explains that a warrior goes through the cairn to defeat an "Eater of Light", but with the invading Roman army, she allowed one to escape to fight them . Bill leads the surviving legion away from the creature and end up reuniting with the Doctor and Nardole . The Doctor works out a plan to lure the Eater back to the portal during daylight, but it requires someone inside preventing the creature's escape . Once the creature is trapped, The Pict and the Ninth Legion sacrifice themselves to stop the creatures . Back in the TARDIS, Missy awaits their return, to the surprise of Bill and Nardole . The Doctor tells Missy that he has hope she will turn good . </Td> </Tr> <Tr> <Th> 275a </Th> <Td> 11 </Td> <Td> "World Enough and Time" </Td> <Td> Rachel Talalay </Td> <Td> Steven Moffat </Td> <Td> 24 June 2017 (2017 - 06 - 24) </Td> <Td> 5.00 </Td> <Td> 85 </Td> </Tr> <Tr> <Td_colspan="8"> In a flash forward, the Doctor stumbles from the TARDIS into a snowy landscape and begins regenerating . Earlier, the Doctor proposed to test Missy by having her answer a distress call . They arrive via TARDIS on a colony ship reversing away from a black hole . They are held at gunpoint by Jorj, who demands to know which of them is human, and Jorj shoots Bill . The Doctor, Missy, and Nardole learn that a few days ago, some of the crew had gone down to the ship's lower decks but never returned . Jorj claims the ship is otherwise empty, but the Doctor shows there are thousands of humans, descendants of the crew: due to time dilation, time moves much faster on the decks furthest from the black hole . Bill awakens in a hospital, having been fitted with a replacement heart . Razor, the hospital caretaker, explains that some of the patients are waiting to be "upgraded" to escape the ship's polluted air . Years later, they see footage of the Doctor coming down the lift, while only a few minutes have passed for the Doctor . The Doctor, Nardole and Missy arrive and discover the origin of the colony ship: Mondas . Razor approaches Missy and reveals himself to be her previous incarnation, formerly known as the Master . The Doctor and Nardole find a Cyberman who reveals itself as Bill . </Td> </Tr> <Tr> <Th> 275b </Th> <Td> 12 </Td> <Td> "The Doctor Falls" </Td> <Td> Rachel Talalay </Td> <Td> Steven Moffat </Td> <Td> 1 July 2017 (2017 - 07 - 01) </Td> <Td> 5.29 </Td> <Td> 83 </Td> </Tr> <Tr> <Td_colspan="8"> Escaping to a higher floor of the ship, the Doctor tries to comfort Bill, who has retained her humanity, though this is wearing thin . This floor of the ship is a simulated countryside, where the group helps defend the villagers from the oncoming Cybermen . Knowing they are outnumbered, the Doctor attempts to convince Missy and the Master to help him . They refuse, though Missy seems conflicted . Hoping to save the villagers, the Doctor tells Nardole to take them to another floor while he sacrifices himself . Bill opts to stay with the Doctor, and Nardole says goodbye, taking the villagers to safety . Elsewhere, before escaping to their TARDIS, Missy betrays the Master to help the Doctor by stabbing him in the back, triggering the regeneration process . He shoots her in return, killing her and preventing her regeneration . The Doctor fights off the Cybermen, but is severely wounded in the process . He proceeds to blow up the whole floor, killing himself . Bill survives, with Heather appearing before her . They kiss, and Heather reveals she has changed Bill into her species so she could live on . The two take the Doctor's body back to his TARDIS, before she and Heather leave to see the universe together . The Doctor awakens as the regeneration process begins . He attempts to stop it, and exits the TARDIS into a snowy landscape, where he is greeted by the First Doctor . </Td> </Tr> <Tr> <Td_colspan="13"> Special (2017) </Td> </Tr> <Tr> <Th> 276 </Th> <Td>--</Td> <Td> "Twice Upon a Time" </Td> <Td> Rachel Talalay </Td> <Td> Steven Moffat </Td> <Td> 25 December 2017 (2017 - 12 - 25) </Td> <Td> 7.92 </Td> <Td> 81 </Td> </Tr> <Tr> <Td_colspan="8"> Wandering back to his TARDIS at the South Pole, the First Doctor refuses to regenerate . He encounters the Twelfth Doctor outside his own TARDIS in a similar state of mind . The pair are approached by a displaced, confused and injured First World War British captain . All three are abducted by a spaceship, where inside they meet Bill Potts . They are offered freedom by the ship's glass - like holographic pilot in exchange for allowing the return of the Captain . They escape and take the First Doctor's TARDIS to Villengard . Alone, the Twelfth Doctor meets with the rogue Dalek Rusty . Given access to the Dalek Hivemind, the Doctor learns that the pilot and its ship, known as Testimony is designed to extract people when they died, and archive their memories; Bill is one such avatar . The Doctors agree to return the Captain to his timeline, which happens to be mere minutes before the Christmas truce . The First Doctor informs the Twelfth that he is prepared to regenerate, and returns to his TARDIS . After being alone with Bill's avatar, the Doctor returns to the TARDIS and regenerates after relaying advice to his next incarnation . After the Thirteenth Doctor examines her reflection, the TARDIS suffers multiple failures . Tumbling out of the ship, the console room explodes and the TARDIS dematerialises, as the Doctor plummets towards the Earth . </Td> </Tr> </Table> <Tr> <Th> Story </Th> <Th> Episode </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> UK viewers (millions) </Th> <Th> AI </Th> </Tr>

When does twice upon a time come out