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Arachnids in the UK was the fourth episode of series 11 of Doctor Who.

The Thirteenth Doctor finally returns Graham, Ryan and Yasmin to Sheffield, just half an hour after they had left. Notably, these new companions actively choose to travel with her at the end of this episode.

This episode marked the debut of several recurring characters of the Whittaker era. Yasmin's mother Najia Khan, father Hakim Khan and sister Sonya Khan made their first appearances, as well as ruthless businessman Jack Robertson, who would appear again in the 2021 story Revolution of the Daleks.

This episode also marked the debut of a new design for the Time Vortex. Unlike other recent versions, where the TARDIS flies through one single pathway, this version shows multiple different paths.


The Thirteenth Doctor finally manages to bring her friends home, but with more time alone on the horizon, she soon discovers that something unnatural has happened to the eight-legged population of Sheffield. Why have they converged on an unopened hotel, and why is there a man going around like he owns the place?


In the ballroom of a lavish hotel, businessman Jack Robertson is talking with his personal assistant Frankie Ellish; he wonders if the reason she is unable to take care of something for him is a lack of funds. However, Frankie tells him that the problem isn't money, but the sheer scale of the problem; not to mention that maintaining confidentiality will be next to impossible. Taking care of this problem risks exposing them, and him. Jack's bodyguard Kevin enters, informing Jack that his private plane is waiting for him; however, Jack tells him that the plane will leave when he tells it to. Jack reminds Frankie that they're family, but stops to ask how they're related again as he's forgotten. Frankie reminds him that she married his niece, making her his niece-in-law. Jack tells her that it's because they're family that he trusts her to get things done.

Another woman walks into the room, much to Jack's surprise; he asks Kevin how she managed to get in, to which Kevin says is because he came to tell him about the plane. The woman introduces herself as Najia Khan, explaining that she will be working at the hotel as the general manager. Robertson is confused by her presence as he gave the staff two days off. Najia says she came in early to do some prep work. Frankie once more tries telling Robertson that his idea isn't safe. Robertson snaps, telling Najia she's fired and to leave. He tells Frankie to take care of the problem and walks out.

Time Vortex AitUK

The TARDIS flies through the vortex.

The TARDIS flies through the Time Vortex at amazing speed; it exits out of one pathway and into an area of multiple different ones. It flies down one of the available paths. Inside the TARDIS, the ride is very bumpy as the Thirteenth Doctor works at sparking controls to get the TARDIS to cooperate. Graham wonders if the Doctor can actually control her time machine, to which she admits "very nearly" as the TARDIS tends to be mischievous.

The TARDIS materialises in present-day Sheffield, present-day Earth, outside the Park Hill housing complex. The Doctor pokes her head out of the TARDIS, happy to finally have gotten her companions back home. Yaz, Ryan and Graham exit after the Doctor, happy to be back. Yaz checks her phone, noting that she doesn't have any new messages. The Doctor tells her that its because the TARDIS has landed half an hour after they initially left. Yaz notes that they are right outside her apartment, with Ryan noting how weird it is as he and Graham only live a short distance away. Graham tells the Doctor that it's been an honour to meet her; a compliment she returns.

Ryan wonders what the Doctor will do next, to which the Doctor says she'll resume travelling now that she has her TARDIS back. Seeing how sad the Doctor is to part ways with them, Yaz asks if she wants to join her for tea. The Doctor's face brightens; she accepts the invitation, shutting the TARDIS doors. Yaz also invites Ryan and Graham, but Graham declines, deciding he wants to stop by home first. Ryan offers to come with him, but Graham kindly tells him that he needs some time to himself.

Yaz leads the Doctor and Ryan top her family's flat, passing a woman in the hall. The woman is noticeably concerned and keeps trying to get the resident of a nearby flat to answer the door. The Doctor notices but dismisses the thought. Yaz leads the Doctor and Ryan in her flat; she calls out to her family, telling them she brought friends. Yaz then mutters to the two that she hopes they're out. However, Yaz is out of luck; her father, Hakim, pops around from the kitchen, surprised that she's brought friends home for tea. He calls to Yaz's sister, Sonya, who walks out to meet them. Unlike Hakim, Sonya is sceptical that they are Yaz's friends, asking if she paid them to pretend to be her friends.

Down the road, Graham stands outside his house, looking on, When he finally decides to enter, Graham looks around and imagines Grace playfully scolding him to remember where things are and when the trash is to be taken out. Graham tells his imaginary wife that he has so much to tell her about his travels.

Flat 34, Park Hill (Arachnids in the UK)

Tea at the Khan family's flat

Back at the Khan's flat. Yaz, Sonya and Ryan sit at the table, while the Doctor looks around and marvels at the idea of flats. She thinks to herself that she could buy a flat, and also admiring the pink sofa, and generally rambling on; she then asks Ryan if she was being weird. Once he confirms it, the Doctor says she's trying small talk but is a bit nervous. She then notices a large pile of junk in the room, wondering if Hakim collects it like stamps. Much to Yaz's annoyance, Hakim says that its evidence as there has to be some kind of conspiracy. The Doctor smiles, loving a good conspiracy. Yaz tells her father that she asked the police to look into it. Sonya jokes that Yaz is married to her job, to which Yaz snidely remarks Sonya is unemployed.

Yaz gets a call from her mum, Najia asking her to come and pick her up; she also tells Yaz not to tell anyone as they'd only get worried. When asked about the call, Yaz lies that her mum just forgot something. Hakim tells her to hurry back as he'll be making pakora for tea. Yaz gives a frightened look, telling him not to as he's really bad at making it. As Yaz leaves, the Doctor thinks about how the sisters mock each other, reminiscing about having once had sisters. She then notices a piece of mail that states their neighbour has gotten a parcel for them by mistake. Hakim confirms it, stating that he's tried to get it, but hasn't been able to get an answer from his neighbour for days. Seeing a chance to pass the time, the Doctor offers to get the parcel "while [he] makes [his] terrible pakora."

Back at Graham's house, he is smelling Grace's jackets. His imaginary Grace chides him for doing something so silly as it won't change the fact she's gone. Graham hears a thud from the attic and heads up to check. He finds it filled with webs and an unusually large shed spider skin on the floor.

Flat 27 (Park Hill)

The Doctor discovers something is wrong.

At Yaz's flat, the Doctor and Ryan leave to collect the parcel. They find the woman from earlier still outside the flat, which is the very same one they need to visit. The woman introduces herself as Jade, explaining that one of her colleagues, Anna, hasn't been to work in a few days; she hasn't called in sick, so this is concerning. The Doctor asks if she's concerned about Anna enough to force her way in, to which Jade confirms. The Doctor helps by unlocking the door with the sonic. All three enter the flat, finding it covered in spider webs. The Doctor doubles-checks how long it's been since Jade heard from Anna, which is only a few days. Ryan notes that it looks like more than a few days from the lack of cleanliness.

They head down to the bedroom. They open the door to find a silhouette of a person of the bed. Jade calls out to Anna as Ryan pulls back the curtains. The lights reveal a dead Anna on her bed, covered in spider webs. A panicked Ryan joins the Doctor and Jade, asking if those spiders aren't supposed to do that. The Doctor tells him that's the wrong question; the question is where is the spider that did this? They carefully approach a wardrobe and open it; however, nothing is in it. The Doctor and Jade move for the door as Ryan checks under the bed. Something moves, startling him back to the door. A spider the size of a small dog crawls out. Jade and the Doctor note that its domestic, but way too big. They very carefully open the door and rush out. The Doctor orders Ryan to block the door while she gets some things. A very panicked Ryan tries calming himself but finds the spider trying to reach under the door.

Jade joins the Doctor as Ryan yells for her to hurry. Jade realises that the spider got in through the rubbish chute, wondering if they can force it back out through there. However, the Doctor is against the idea; it will be a bigger threat if released into the public. They have to trap it in here until they can devise a better way to deal with it. The Doctor takes some vinegar and garlic from the kitchen and spreads it on the floor, walls and ceiling in a square. She calls Ryan up and he rushes to join them. The Doctor explains that spiders smell through their feet; the strong smell of garlic and the acidity in the vinegar will dissuade the spider from following them. The spider approaches and just as the Doctor explained, the barrier works; she tells the spider to say put while she deals with this.

In the Khans' flat, Hakim and Sonya are waiting for Yaz, the Doctor and Ryan to return. Hakim notes its taking them a long time to retrieve a parcel. Sonya notes that Yaz always has the weirdest friends.

Yaz drives up to the hotel to pick up her mum, meeting her in the lobby. She warmly hugs Najia who is curious as her daughter only saw her earlier that morning. Yaz notes the nice looking hotel and is impressed her mum works here, but Najia tells her that she just got fired. When Yaz asks who fired her, Robertson enters with his bodyguard Kevin hostility pointing a gun at both Khans. Robertson states that he fired Najia, but she is still there (now trespassing) and called in another person. Najia tells the arrogant man that she called her daughter for a ride home. However, Yaz demands to know why. Mistaking her for a teenager, Robertson says she should be in school and that if he hadn't fired Najia, he would have ten minutes ago when he saw the rooms. Both Yaz and Najia demand to know what he means.

The Doctor, Ryan and Jade rush out of the flat and lock the door behind them. Graham joins them, telling the Doctor about what he found in his house. Catching her breath, the Doctor notes Jade wasn't surprised by the spider webs in the flat and demands to know what she knows. Jade explains that this wasn't the first incident; something is wrong with the spiders in Sheffield. She then explains that she's a scientist that works with arthropods and arachnids. As they walk off, Graham hands Ryan a letter addressed to him from his father that he found at the house; Ryan simply pockets it. Jade explains that her lab isn't far from there; they head for the lab.

Wood Hill area map (AITUK)

The Doctor draws a map marking the spider's location.

At Jade's lab, she explains her lab has been working on enlarging spiders to harvest their web as its stronger than steel and more durable than Kevlar. Ryan tells Jade that it's not making him like them any more. The Doctor says Jade is right about webbing; if it was round thick as a pencil it can stop a plane. Graham wonders if the Doctor is serious; she tells him that she's had to deal with it with Amelia Earhart. Returning to the problem at hand, the Doctor asks Jade to clarify what she means by something being wrong with the spiders. Jade pulls out a map, which she has marked for unusual activity; species not supposed to be out during this time of the year, large numbers and massive web-building. What's been perplexing her is whether this all this out anger, confusion or fear? However, the Doctor instead realises the spiders are sending a message, grabbing a marker and connecting the dots on the map. It forms webs with an empty area in the middle: Robertson's hotel.

At the hotel, Frankie has finally reached the end of her patience with Robertson's utter lack of concern about the problem he wants dealt with; she walks down a basement corridor, unaware of the large amount of webs due to the faulty lights. She opens a door marked out of bounds to the public and enters a subterranean location. Frankie uses her mobile phone to record a testimony to reveal a secret Robertson has been keeping from the public. However, she notices something further in that scares her; exclaiming in fear, Frankie is grabbed by a spider off-screen and pulled away. Her phone is left behind with the image of spider webs hanging above.

In the meantime, Robertson shows Najia and Yaz a room with a bed covered in webs, which he blames on her for poor housekeeping. He fires her again, noting it's time for his scheduled bathroom break; he and Kevin head for the next room. Robertson tells them that once he's done, Kevin will escort them off the premises. Najia tells Yaz that the room wasn't like this the previous day. Suddenly, both her scuttling sounds from the wall. Yaz slowly walks over and leans on the wall to listen, unaware that a large spider is on the other side. Najia gets a call, telling Yaz its a doctor; Yaz takes the call, knowing its the Doctor. The Doctor asks Yaz if she's at the hotel, to which Yaz confirms; the Doctor asks Yaz to let her group in.


Kevin fires at the spider.

In the bathroom, Robertson is washing up. He hears an odd sound coming from the tub; he looks at the drain, finding nothing wrong. Dismissing it, he returns to washing up. Suddenly, the tub starts cracking and then "explodes" with Robertson backing up to the door; he yells in panic as a giant spider crawls out. Kevin opens the door, gun ready; Robertson shuts him in with it. In the lobby, the Doctor greets Najia with a hug; she tells her that she made an awesome human. Everyone hears gunshots, immediately racing to find the source. Robertson asks Kevin through the door if he killed the spider; he cracks open the door to see the spider on top of Kevin and silently closes the door in terror. He then realises that his phone was in there; unfortunately, Kevin grabs it in his futile attempts to escape as the spider drags him back into the hole.

Robertson runs back into the hall, where the Doctor uses the psychic paper to pass herself off as a "Crisis Investigator". She asks for a full explanation about what he just saw; Robertson recaps very clearly what happened. The Doctor takes Yaz with her to investigate. Robertson remains with the group, being recognised by Graham and Ryan. In the bathroom, the Doctor decides to poke her head down the hole to see what's down there. Hearing a skittering, she turns to see a spider and rushes back out of the hole; she pulls Yaz with her back to safety. The Doctor tells everyone they need to get out of the hallway, as it is too dark and abandoned; spiders love places like that. However, Robertson and Ryan are for leaving altogether. Everyone agrees and starts running. Robertson asks Graham who they are, being told that "run now, ask questions later" is the best way to stay alive. Everyone reaches the lobby, only to find that the spiders have webbed up the entrance to trap them. Robertson tries passing this off as some kind of Eco-protest against his hotel but isn't fooling himself. Realising the spiders intend to trap them as prey, the Doctor asks Najia where the brightest room is in the hotel - the kitchen.

Thiteenth Doctor in hotel kitchen (AITUK)

The Doctor takes charge

Everyone races into the kitchen, with the Doctor noting they need to find a way to deal with the spiders. Robertson starts to interrupt but then realises that the Doctor just said there's more than one giant spider on the loose in the hotel. The Doctor initially mistakes Robertson for Ed Sheeran, finding out Robertson is just another greedy, egocentric businessman. Jade adds Robertson is even planning to run for President of the United States just because he hates Donald Trump; Robertson is notably disturbed by the use of the name. After her companions firmly say she's in charge, the Doctor begins thinking, asking for facts to help solve the problem. The Doctor tells everyone that they need to capture a spider. Robertson goes wide-eyed, telling them that he's not going anywhere near one.

In the hotel hallway, Graham is talking to himself. It draws a spider, which slowly approaches him. However, before it can do anything, Ryan slams a pot over it and Graham slips a lid underneath to trap it. Ryan looks behind Graham in fear, telling him to run. They proceed to run back to the kitchen as a horde of spiders crawl after them. Back in the kitchen, Jade examines the specimen, wondering if its the biggest one. Ryan tells her that there's no way that they're going back out there to find another one. Jade hesitantly tells him that it's most likely the case. The Doctor asks to be shown a map of the hotel.

In a hotel room, the Doctor examines a blueprint, which Robertson says isn't correct as his panic room isn't on it. The Doctor asks Najia if she's ever had a problem with spiders before, as her neighbour had a giant spider in her flat; so far the only link between the two incidents is Najia. Robertson takes this as Najia being directly involved, threatening to sue her for all she's worth; however, Najia firmly tells him that she has no more idea what's going on her than he does. Najia asks Yaz who the Doctor is, to which Yaz asks her to be silent as they have bigger problems than introductions right now. However, Najia is insistent; even Robertson wants to know, out of amusement. Yaz tells her that she owes the Doctor her life, quite a few times over. Najia briefly wonders if they're romantically involved, much to the Doctor's own confusion; Yaz says they're' just friends. Najia then remembers that Frankie was telling Robertson that something he wanted taken care of wouldn't be safe; the Doctor catches on and asks what he's hiding. Robertson reveals that all his hotels are built on re-purposed lands, but he has no clue what this land used to be. Najia tells him that it used to be a mining area, meaning there are mines below.

Memorising the map, the Doctor leads Yaz, Najia and Jade to the basement corridor; Robertson follows behind them, protesting they're going down there. They arrive at the door Frankie entered, but it's locked; however, it's not a problem for the Doctor. The Doctor opens the lock with the sonic and everyone follows her inside. Yaz finds a fuse box and gets the power back on, revealing a tunnel covered in webs. Robertson explains that he bought the land and provided a first class hotel in place of the defunct mine, as perfect business plan. They come across two cocoons, which contain the bodies of Frankie and Kevin. Jade explains that spiders aren't supposed to do this; they're not supposed to store prey to be eaten later. The Doctor explains that the spiders are out-sized and confused, but the more important question is whether the mines are the target of the spiders or their base, because they connect to the rest of South Yorkshire.

The Doctor smells something horrid further in, finding a cavernous area of the mine has been used as a landfill. Though he attempts to deny having any knowledge of this, Robertson relents and reveals that his waste disposal company JLR Disposal cut corners to make their bottoms lines. However, he then defends that he only signs the contracts, expecting other people to do their jobs. The Doctor is horrified by the lack of concern by the men who dumped all the hazardous material down here; its effectively toxic waste, building up and getting more toxic. The smell is even reaching Park Hill flats, which is what makes Rakim so suspicious. Jade then reveals that JLR takes their lab waste; she concludes her lab may have believed some spiders were dead, but were actually barely alive and ended up in the toxic waste. The Doctor then realise that their already augmented lifespans were extended further by the waste, allowing them to grow beyond the intended size and they've been feeding on the waste, growing stronger.

The Spider Mother in the Ballroom (AITUK)

The Spider Mother in the Ballroom.

Graham and Ryan head to the ballroom in search of a new specimen. Ryan reveals that he read the letter; his father wants him to come live with him, since Graham isn't his proper family. Ryan says he didn't like how his father said Graham wasn't his proper family, making him happy. However, Graham realises they didn't check the ceiling when they entered. They shine their torches up and find a giant spider on the ceiling. They turn and run, as it lands with a loud thud. It gives chase, but they manage to slam the doors in its face.

Everyone meets back in the kitchen. The Doctor wonders what they found. Graham explains that the spider was the size of a large van; the Doctor concludes its the mother spider, and the rest are its babies. The Doctor then realises that the reason that the spiders have suddenly appeared, is because every living thing in the universe has the instinct to come back home. She tells Jade that Anna likely had spider pheromones on her from working at the lab, accidentally calling to a spider that left to hunt for food. The pheromones of the giant spiders were what was disrupting the spider ecosystem. Robertson doesn't' care about the specifics, asking how the plague in his hotel is to be dealt with. The Doctor asks to be shown his panic room.

Unlocking his panic room, Robertson rushes everyone in and shuts the door. Ryan asks what's in the boxes inside the room. Robertson explains they contain six months of food and water, along with entertainment. He then brightens, remembering he has enough guns to arm each of them twice. Ryan tells him the Doctor is against guns. Robertson is utterly dumbfounded, asking what's wrong with the UK's policy on weapons; he believes the "civilised" way to deal with a threat is to shoot it. The Doctor says they are going to lure the spiders with the promise of food and lock them inside, allowing them to die off in peace. As spiders sense food through vibrations, the Doctor asks if anyone has any ideas. Ryan complies, playing Stormzy's song "Know Me From" over the speakers in the hotel. The spiders head for the source of the noise, all the while, with Ryan and Yaz by the gate to the panic room area, and Robertson by the actual door.

Jack Robertson

Robertson coldly defends his actions.

Once the spiders are secured, everyone heads to the spa, where the Doctor tells them to stock up on essential oils. She tells them to meet her in the ballroom. They enter, armed with spraying packs; the Doctor explains that its diluted strong-smelling oils, which they can hopefully use to herd the spider outside. However, Jade stops them; she notes the mother spider has gotten too big to breathe efficiently. The Doctor apologises to the spider for its fate, just as Robertson enters holding a gun; despite the Doctor's pleas, he shoots it. The spider roars in pain, falling over dead. Angered by his actions, the Doctor tells Robertson that the spider wasn't a threat; it was already dying. Robertson passes it off as a mercy-killing, telling the Doctor that he doesn't need her permission. He states that his kind of thinking will get him into the White House one day. As Robertson walks off, Graham can only quip "God help us".

That night, Ryan heads out to say goodbye to the Doctor. Graham lingers, as his imaginary Grace tells him to get going. In her flat, Yaz listens to her family bicker; her mother telling her father to get rid of the trash. Hearing they're out of bread, Yaz offers to go get some. Najia thanks her, telling Yaz that she better tell her about who the Doctor is when she gets back. Yaz smiles, stating she will when she gets back.

Outside the TARDIS, Yaz, Ryan and Graham have gathered. Graham knocks on the TARDIS and the doors open on their own. They walk inside, finding the Doctor at the console. She asks if this is really goodbye. However, Graham states that he's changed his mind, as he wants to see more of the universe to help him move past his grief. Ryan doesn't want to go back to his job, having found life in the TARDIS to be more fulfilling. Yaz states that travelling with the Doctor is better than being driven insane by her family. Happy to not have to travel alone or find a new companion, the Doctor welcomes her friends back to the TARDIS. However, finding that it doesn't sound right, the Doctor asks if Team TARDIS sounds better; they agree. Together, they pull the lever to start their new adventures through time and space.



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.





  • Giant spiders, and their mother have infested Robertson's hotel.
  • Jade and Anna are studying arachnids and arthropods.
    • One of the spiders is given the Latin name Hirsutus.
  • Spider-web can be as strong as kevlar, as indicated by Jade.
  • The Doctor says that she and the others are like flies.


  • Najia briefly works as General Manager for Robertson Luxury Hotels.
    • Robertson says that it is only one in a very successful chain of hotels which is only one small part of his business portfolio.
      • The one in Yorkshire used to be a coal mine.
  • Royal Mail have delivered a parcel which needs collecting from Flat 27.
  • JLR Disposal gets rid of waste.
  • On the bottle the Doctor carries it says Trapex Export.
  • Robertson says he's gonna get into the White House by any means.


  • Ryan plays "Know Me From" to attract the spiders.
    • The music is on Raze, which Ryan calls "Sheffield's sickest grime station!"


Food and beverages[]


Story notes[]

  • This story introduced the new version of the Time Vortex, providing an in-depth view of the TARDIS flying through it.
  • While the Doctor says in this episode she's never had a flat before, previous stories such as PROSE: Verdigris and PROSE: Endgame indicate otherwise.
  • This is the second Doctor Who story to feature giant spiders after Jon Pertwee's regeneration story Planet of the Spiders 44 years previously.
  • The plot of the episode is similar to the films Ice Spiders and Eight Legged Freaks due to using both the themes of scientific blunders from the former and toxic waste mutating normal sized spiders from the latter, along with the spiders using an abandoned mine as their lair.
  • The title of this episode is a play on the Sex Pistols song title Anarchy in the UK, and was suggested in the writers' room by Vinay Patel.[1]
  • Almost every science fiction fact about spiders mentioned or done in the episode has its ground in real-world science.[2]
  • Internationally renowned zoologist and conservationist Dr Niall Doran was consulted for this episode.[3]
  • Though maybe not a surprise, Chris Noth has admitted he loosely based his character Jack Robertson on real-world US President Donald Trump. He also hoped for the character to return, saying that maybe Jodie's Doctor could face off against "President Robertson" in the future.[4]
  • In the Brazilian dubbing, the reference to Ed Sheeran was changed to Silvio Santos. Silvio Santos is a Brazilian businessman, TV entertainer, and the owner of the TV channel SBT. He also tried the presidency in the 1989 election.


  • 6.43 million (UK overnight)[5]
  • 8.22 million (UK final)[6]
  • 900,000 (US figures)[7]

Filming locations[]

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.
  • The Doctor instructs Ryan to stall the spider by blocking the door, but the door doesn't open outward.
  • Before The Doctor draws on it, some locations dots on the web map disappear between wide & close up shots.


Home video releases[]

DVD & Blu-ray releases[]

  • This story was released as part of the Complete Eleventh Series boxsets on DVD and Blu-ray in region 1/A on 29 January 2019, in region 2/B on 14 January 2019 and in region 4/B on 6 February 2019.

Digital releases[]

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

External links[]