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Under the Lake was the third episode of series 9 of Doctor Who.

It saw the series revisit the concept of ghosts and hauntings, last explored in the television story Hide in 2013. The episode poses another explanation for the apparitions, in this case as resurrected transmitters of an alien presence's signal. It also continued the thematic concept of the Doctor apparently facing death, with the end of the episode setting up yet another opportunity for the Doctor to reflect on his mortality.


Arriving on an underwater base under attack, it's up to the Twelfth Doctor and Clara to save the frightened crew. But also onboard is an alien spaceship, and the base is being haunted by the most impossible of things.

The Doctor's deepest beliefs are challenged when he encounters something he cannot explain. Can it really be possible? Can ghosts be real?


In an underwater mining facility based in Scotland, 2119, designated the Drum, the captain, Moran, is recording a log in his journal. Moran states that the team has discovered a small craft located on the bank, and, as they are unable to analyse it from within the base, they have brought it inside, where he and the crew will investigate.

A crew member named Lunn interprets the sign language of another crew member, Cass, saying that the reason for its sudden appearance is due to underwater movement and shifts on the floor of the lake. Another crew member named Pritchard recommends they discuss ownership of the spaceship, prompting Moran to tell everybody to stop calling it a spaceship, as they don't know what it is. Bennett, another of the crew, is adamant that it's not technology that could have existed back in the 1980s.

The crew enter, and Moran notices something inside the craft, asking Lunn to hand him a torch. Lunn does so, but glimpses a ghostly figure reflected in the glass. He reluctantly hands Moran the torch. Moran investigates four strange markings on the wall, whilst Lunn asks Cass why he shouldn't go inside. Whilst they bicker, Pritchard cries out as he glimpses the ghost, accidentally starting the engines. Moran pushes Cass out of the way of the boosters' range but is struck by the blast, forcing the crew to retreat, leaving him behind.

O'Donnell, another crew member, bangs on the sealed door, demanding they go back for Moran, but is told it is impossible by the rest of the crew. She yells at Pritchard for messing with the controls but is interrupted as Cass screams. She turns, startled to see a ghostly Moran, with gaping back holes for eyes hovering in front of her. The same figure named Albar Prentis appears, and the pair reaches out to the crew...

Three days later, the facility is a wreck, being seemingly empty. The TARDIS appears, with the Doctor stepping out, realising that they are in the 22nd century. The Doctor notes that the TARDIS is in a foul mood as if something nearby is upsetting her. Laughing, Clara pops her head out of the TARDIS, asking if they can go back to the planet where people with long necks have been celebrating New Year's for two centuries; she left her sunglasses and most of her dignity there. Still amused, Clara accuses the Doctor of "itching" to save a planet. He smiles back, deciding to check out the area.

They investigate the mess hall, which has evidence of a really bad fight with utensils and furniture throw about. Finding a knife lodged in a wall, the Doctor tells Clara that she got her wish for a mystery. She wonders how long the place has been empty since many supplies are missing from the mess hall stock. The Doctor sticks his finger in a mug of coffee, explaining that the fight happened right hours ago.

They resume searching for a crew, finding the two ghosts kneeling in the corridors. The Doctor calls out to them and the two ghosts approach, startling the duo. Clara is calmed by the Doctor, who thinks that the ghosts are only curious about them; the ghosts walk down the corridor and through a wall. The Doctor and Clara follow, finding themselves in the hanger; Clara wonders about the strange vessel the crew found, thinking it could be a government project from this era. However, the Doctor confirms that it's alien in nature. They go inside, finding it undisturbed since the crew first investigated; they find the strange writing on the wall. The Doctor is shocked by this, as it isn't being translated by the TARDIS translation circuit.

However, before he can ponder this further, Clara draws his attention to the outside of the ship, where the ghosts have reappeared. The Doctor greets them warmly, wondering if they wanted them to see this strange writing. The ghosts do not respond, only walking over to a wall to grab weapons. Clara notes that this is not going well. The Doctor wonders if Clara said anything to offend them, as she once even got into a fight with Gandhi. Moran fires a harpoon gun at them but misses. The Doctor and Clara run out of the hanger; the ghosts follow them through the walls but are forced to leave their armaments behind as they are not intangible like them.

Now back in the corridors, they run away from the ghosts. At the end of the corridor, O'Donnell opens a door, yelling for them to enter. They comply and the door is slammed behind them. The room is filled with living supplies and the remaining six members of the crew. A smug man by the name of Pritchard tells them that if they don't work for Vector Petroleum, they are in big trouble. The Doctor brandishes the psychic paper and introduces himself and Clara. Shocked by what he sees on the psychic paper, Pritchard yelps that they're from UNIT; "Well, if that's what it says." the Doctor passively says. O'Donnell shakes his hand, happy to meet a Doctor. The Doctor asks what the ghosts are, dismissing the idea they are ghosts; he asks to know who's in charge, so he can ignore them. Lunn explains that Cass is, but Pritchard claims to be as he's from management.

The Doctor ignores Pritchard, asking what happened; Lunn begins translating for Cass, but the Doctor tells him that he can understand sign language. Cass begins explaining, but the Doctor asks her to stop; he thinks he deleted sign language from the TARDIS for Semaphore. Lunn resumes translating; the mole alien killed Moran as soon as the ship got brought on board and the ghosts have pretty much been trying to kill them since. The crew hide out here in the Faraday cage as the ghosts cannot enter it for some reason. The Doctor notes how odd it is for the alien ghost to be aggressive as Tivolians are so cowardly, "They wouldn't even say boo to a goose." A recorded voice announces that day mode is on. Everyone starts leaving the room, confusing the Doctor; O'Donnell explains that the ghosts only come out at night.

Everyone returns to the hanger, with the Doctor curious as to why they haven't abandoned the base. Pritchard takes credit for that, explaining Vector Petroleum would lose tons of money if they abandoned the base. The Doctor calls Pritchard an idiot for not valuing human life over money; he recaps the entire ridiculous situation, sarcastically asking if anyone has a peanut allergy. The Doctor goes back into the ship, asking where the missing parts are; this confuses the crew as they haven't touched the ship since they brought it on board. The Doctor explains that a power cell is missing and so is the suspended animation chamber for the pilot. He begins to ramble on what he's observed about the ghosts, grinning more and more as he comes to a conclusion. Clara, having caught on to his train of thought, wonders if he's actually thinking...

"They're ghosts!" the Doctor exclaims back in the control room. Clara points out that he completely shot down the idea of ghosts. However, the Doctor counters Clara, telling her that there were no such things as socks, smartphones or badgers until they suddenly did exist. He further explains these things are not Autons, Flesh avatars or Nethersphere copies; these people are actually, truly dead beings. Met with silence, the Doctor wonders why everyone is staring at him; they explain Moran was their friend. Clara tells him to bring out his cards. Realising Clara is right, the Doctor pulls out a stack of cards with kind and apologetic things written on them.

Annoyed the Doctor is taking too long, Clara takes the right one out and the Doctor reads it off, promising to solve Moran's murder. With that done, the Doctor resumes being excited at the idea of wrestling down a ghost and asking it questions about what it's state of existence is like. He does note he subconsciously noticed the ghost can only handle metal objects. Suddenly, the base announces that it's going back into night mode.

As the others prepare to return to the Faraday cage, O'Donnell notices Pritchard is missing and yells over the speakers for him to get to safety. However, Pritchard was out searching for the missing power cell; greedy, he wanted to find it to gain favour with his employers, along with the rest of the alien tech. Taking off his diving helmet in the decompression chamber, Pritchard notices a figure outside and assumes it's Bennett. However, to his horror, it's Moran and the Tivolian. Before Pritchard has a chance to put his helmet back on, Moran opens the gate and water starts rushing in.

In the galley, Clara and Bennett, while gathering supplies, notice Pritchard is in the room with them, with his back turned to them. They then notice a corpse floating outside the window; Bennett begins shouting there was a man overboard, but Clara stops him as the corpse rotates to reveal it as Pritchard. Right as Pritchard picks up a chair to attack them with, the base suddenly goes back into day mode; O'Donnell managed to fix the problem and restore the system to normal. Back in the control room, everyone watches footage of Pritchard's death. The Doctor notes the ghosts got smarter; they've figured out how to use the base to kill since the Faraday cage keeps them out. Since they can only come out at night, they reprogrammed the base's timer to trick everyone into a false sense of security.

The Cloister Bell begins ringing from the TARDIS. The Doctor and Clara race back inside, where the lights in the control room are flashing red in rhythm of the ringing of the bell. Clara is confused; the Doctor explains "you live and you die; those ghosts are a contradiction." This is why the TARDIS was upset when they got here; she wants to get away from the ghosts. Clara asks him what they should do. The Doctor calmly turns a crank, shutting off the ringing; he just put the parking brake on to keep the TARDIS still. Clare discards her jacket, ready to head back out. However, the Doctor stops her, explaining that despite the infinite space there is inside the TARDIS, she shouldn't "go native" and start acting like him. Clara thanks him for the words.

Cass (Under the Lake)

Cass with Clara.

They return to the control room, where the Doctor is eager is go ghost hunting. However, Cass now has command without Pritchard in the way; she orders the base abandoned, so they can send down someone to take care of the ghosts. She then adds that the Doctor can stay and do his investigation at his own peril. O'Donnell contacts Topside, only to learn a Morse code SOS was sent for a full medical team. The Doctor takes the phone and states his UNIT security visa; he tells Topside the Drum will be under quarantine.

When asked why he did that, the Doctor tells everyone that the ghosts made that call and "I'm pretty sure it's not so they can make a boy band." The ghosts want people here to kill, but the reason why is still unknown. Remembering the brilliance O'Donnell showed in returning the base to day mode, the Doctor tells her to change it back; they need to capture the ghosts and question them about their motives. He offers everyone the chance to leave, as it will be less of a burden to him; however, he adds that this could be a rare chance to understand something out of the norm. Everyone agrees to help; though Bennett sarcastically adds that they know he will come back to haunt them if he dies.

The plan is simple, use Lunn, Bennett and Clara as bait to lure the ghosts to the Faraday cage; the Doctor, Cass and O'Donnell will monitor things from the control room (being deaf, Cass cannot help with being bait as she cannot be prompted over the radio). Bennett finds the ghosts in the galley, yelling for their attention; they give chase as the Doctor tells him where to go over the radio. As soon as Bennett turns a corner opposite of Lunn, Lunn runs out and becomes the ghost's target. However, when it comes time to pass the ghosts off to Clara, only Moran and the Tivolian follow her; Pritchard is still following Lunn.

Pritchard Ghost

Pritchard's ghost.

The Doctor attempts to get Lunn away to an area he can seal off, but Pritchard catches sight of him just as the door seals. The ghosts enter much to Lunn's horror; he cowers in a corner as the ghost leans in. However, it senses something off and leaves. Lunn tells the Doctor the oddity over the radio. Pritchard rejoins the other ghosts chasing Clara, as she passes them off to Bennett. Bennett makes it to the Faraday cage, where Clara is inside; however, when the ghosts go to attack, they pass right through her. It's a hologram of Clara, not the real thing.

The cage is sealed behind the ghosts by the Doctor, who tells them they need to talk. He sends what he's seeing through the sonic sunglasses back to the monitor in the control room; however, Cass cannot read the lips of the ghosts because of the glare of the window. Despite the protests of everyone, the Doctor enters the cage to give Cass a better look at the ghosts. Moran sticks his hand through the Doctor, who says it's cold before jovially asking if the ghost agrees. Without access to the controls or anything metal, the ghosts are no longer a threat. Cass now has a good view of the ghosts and finds they are repeating the same four words: the dark, the sword, the forsaken, the temple. The Doctor is confused for a moment but then has an epiphany.

Device underwater

Bennett searches the flooded town.

Back in the control room, the Doctor explains that these words are coordinates that are leading to the flooded town outside the base. The meaning of the message is something he hasn't figured out; is it a call for help or an invasion signal. The Doctor then asks everyone if something is still bothering them; after a moment, Cass says it's the temple part of the message. The Doctor uses a map to reveal this message is pointing to an old church, where something commanding the ghosts is in waiting.

Bennett uses a remote-controlled exploration device to go through the flooded town to find the church. Inside the basement of the church lies the missing suspended stasis chamber.

The chamber is brought on-board, with everyone curious. To the annoyance of the Doctor, the chamber has a deadlock seal, which means he can't open it with the sonic; whoever is inside is snoozing away, waiting to be rescued. With no answers, the Doctor decides to think back to when he first arrived to come to a conclusion. When he and Clara first arrived, the ghosts made no attempt to kill them; instead, they lead them to the ship and then attempted to kill them. It's at that moment, the Doctor has a realisation. He runs back into the ship and scans the symbols with the Sonic sunglasses, muttering about how the TARDIS can't translate the writing.

Under the Lake stasis chamber

The Doctor ponders about all the mysteries the Drum has presented him with.

The Doctor walks out of the ship, asking Cass (the next smartest person in the room) if she feels something is still off. She tells him the writing in the ship; he explains they act like magnets, creating a localised magnetic field. The Doctor then asks Clara why he doesn't have a radio in the TARDIS; she explains he turned it into a clockwork squirrel. The Doctor says it's because he once got Mysterious Girl stuck in his head for two weeks; "I was begging for the brush of death's merciful hand." The Doctor calls the words an ear-worm, that quite literally rewrites the synapses in a person's brain. They were not surprised by the message, as it was already in their heads; it's also how the ghosts are getting created. They are not a natural occurrence.

Suddenly, the base starts acting up. O'Donnell explains that messing with the day mode of the base so much has caused the system to malfunction and assume the reactor is in danger of going critical. It's being flooded, which means unless they get to the TARDIS, they are stuck here with the ghosts. The Doctor, Bennett and O'Donnell are the only ones who make it to the other side of the base before the doors seal. He promises to come back for Clara. Back in the TARDIS, the Doctor says that he needs to go back before the flood to find out how all this started. Bennet and O'Donnell are stunned at being inside the TARDIS and it dematerialises.


The Doctor's Ghost - Under The Lake - Doctor Who - BBC

A sign of impending doom...

In the galley, Clara tells Lunn that they need to wait for the Doctor. He always comes through, she usually has to put up with listening to how he did it. Lunn freaks out at something outside the window; its a ghost. However, all three are still in the cage. Clara takes a good look at it, instantly becoming horrified; It's the Doctor, only now a ghost himself...



General production staff

Script department

Camera and lighting department

Art department

Costume department

Make-up and prosthetics



General post-production staff

Special and visual effects


Not every person who worked on this adventure was credited. The absence of a credit for a position doesn't necessarily mean the job wasn't required. The information above is based solely on observations of the actual end credits of the episodes as broadcast, and does not relay information from IMDB or other sources.

Uncredited crew[]

Milk VFX[1]

  • Modeller - Jason Brown
  • Junior Modeller - Gavin Platt
  • FX TD - Dominic Carus, Luca Zappala
  • Lighting TD - Bastien Mortelecque



The Doctor[]

  • The Doctor uses cue cards to give apologies.
  • The Doctor once converted his radio into a clockwork squirrel.
  • The conversion occurred because he could not stand hearing the song "Mysterious Girl" by Peter Andre any longer. Apparently each morning his radio was tuned to an Earth broadcaster that played the song daily for two weeks, which caused the song to replay itself in his mind for the rest of the day.
  • O'Donnell is familiar enough with the Doctor to call herself a fan (why this is so is not explained in this episode, but the next one)



  • The Ministry of Defence and the British Army are mentioned, and stated to have had a facility where the spaceship is found.
  • Vector Petroleum is the company in charge of the Drum.
  • UNIT is still operational. The Doctor states that his UNIT security visa is 7-1-0-Apple-0-0, which is enough for him to be recognised, implying UNIT still acknowledges the Doctor's authority. UNIT is also known enough for the Drum crew to recognize the name.
  • The Drum crew refer to their colleagues above the surface as "Topside."
  • Drum Control is where the rest of the base is controlled.


Food and beverages[]

  • A cup of coffee is seen on a table; the Doctor is able to work out how long it's been there by tasting it.
  • Clara states that the Doctor raved about ghosts "like a kid who has had too much sherbet."


  • The Doctor can no longer understand British Sign Language. He believes it has been deleted from the TARDIS language bank, and replaced by semaphore. Despite this, he nonetheless correctly signs "you're beautiful" to Cass when he attempts to communicate with her (although he thinks he's signing "go ahead").

Popular culture[]


Story notes[]

  • The Radio Times programme listing was accompanied by a small colour head-and-shoulders shot of Morven Christie as O'Donnell, with the accompanying caption "Doctor Who / 8.25 p.m. / Could O'Donnell and her colleagues have fallen victim to undead beings?"
  • The working title of the story and the following episode was Ghost in the Machine. (DWM 492)
  • This was the first episode since The Unicorn and the Wasp not to feature the sonic screwdriver.
  • While ghosts had appeared in the series previously, Steven Moffat wanted them to appear in their most familiar form: as the revenant spirits of the dead.
  • When Toby Whithouse learned that he would be writing a two-part story, he was uncertain about his ability to commit to a pair of scripts, but he finally relented when he was informed that his adventure would be made first, and hence would have few budgetary constraints. In the transmission order, it would ultimately comprise the year's third and fourth episodes.
  • This was one of two ideas that Steven Moffat suggested Toby Whithouse might pursue. For his part, Whithouse had been considering the notion of a curse which passed from person to person, deriving its power from an alien lifeform which inhabited the words themselves. Moffat liked this concept, and he suggested that it should be incorporated into the narrative about the phantoms. Whithouse also wanted to try his hand at an adventure which played with paradoxes and time travel, elements which Moffat had often included in his own scripts.
  • To prevent the ghost story from descending too far into cliche, it was agreed that the setting would be a futuristic base; a space station or a moon outpost were discussed, before it was noted that Doctor Who had only rarely taken place in an underwater facility.
  • The presence of a Faraday cage was inspired by research which Toby Whithouse had undertaken for an ultimately-unused Being Human concept. (Funnily enough, Steven Robertson was a regular on that show).
  • The notion of the ghosts mouthing silent words led Toby Whithouse to develop a character who could read lips. This became Cass, whose inclusion was partly a response to a call for greater diversity and representation in British television and film.
  • Moran was originally called Hicks.
  • Prentis' phantom was a late addition to the script.
  • This two-parter formed Block One of season nine.
  • Producer Derek Ritchie chose Daniel O'Hara to direct, having worked with him on Wizards vs. Aliens.
  • Zaqi Ismail had previously learned British Sign Language to facilitate communication with his deaf sister.
  • Peter Capaldi's mother passed away early in production, requiring him to return to Glasgow to be with his family. As a result, Daniel O'Hara had to hastily rearrange his recording schedule so that the initial days were devoted to material in which the Doctor did not appear.
  • During rehearsals, the actors playing the ghosts found themselves struggling with the black gauze which was meant to obscure their eyes. It was quickly agreed that this effect would instead be achieved using computer animation.
  • A deleted scene explained that the ghosts were powered by a planet's magnetic field, and that they couldn't manifest when the Drum was in Day Mode because the facility's automatic systems generated their own magnetic field, out of phase with the Earth's.


Production errors[]

If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.
  • Recordings of Prichard's drowning portray his words and movement slightly differently.
  • When Clara and the Doctor run from the "ghosts" and are directed to run towards the Faraday cage down a straight corridor, Jenna Coleman ducks below the camera.
  • When the Doctor, Clara and the rest of the crew are in the Faraday cage, speech often doesn't match lip movements between shots.
  • O'Donnell tells the Doctor the TARDIS is on the other side of the flood doors, yet the Doctor nor Clara have told her about it.
    • It is shown that O'Donnell knows about the doctor and had previously used the Drums security cameras. It can be assumed she saw and recognised it.
  • In the scene in which the crew watch Prichard's death, if you pause just before the water floods into the airlock, there is a single frame of a green screen replacing the water.
  • In the second last shot in the episode, with Clara, Cass and Lunn looking outside, there is a boom microphone shadow right across Clara's face.
  • As the Doctor is explaining to the crew about ghosts, between shots, his body position and the lighting change.


Home video releases[]

DVD & Blu-ray releases[]

  • Under the Lake was released as part of the Series 9, Part One DVD and Blu-ray boxsets in region 1/A on 3 November 2015, in region 2/B on 2 November 2015 and in region 4/B on 4 November 2015.
  • It was later released as part of the Complete Ninth Series DVD and Blu-ray boxsets in region 1/A on 5 April 2016, in region 2/B on 7 March 2016 and in region 4/B on 9 March 2016.

Digital releases[]

  • In the United Kingdom, this story is available on BBC iPlayer.

External links[]

Transcript of Under the Lake at Chrissie's Transcripts Site