Knock Knock
Doctor Who Logo 'Knock Knock'
(Story Code 10.04)

by Mike Bartlett
The Twelfth Doctor

“You came here. You signed the contract. And now, it’s time to pay.” – The Landlord

Bill’s friend Shireen introduces her to their new housemates, Harry, Paul, Felicity and Pavel, and together they go hunting for a new place to live. Unfortunately, all the houses are either tiny, have no privacy, or a situated right next door to a giant, noisy factory. Disappointed, the gang leave the estate agent’s and are met by a strange elderly man, who offers them a place to stay. Bill and her friends are only too happy to view the property, and are amazed when the Landlord leads them to a huge mansion with spacious rooms available at a cheap rate, the only caveat being to keep out of the unsafe tower at the centre. The gang sign the tenancy rental contract straight away, although Bill is suspicious about the place… That night, during a thunderstorm, Pavel is the first to move into his room. Putting a classical record on his turntable, Pavel hears a creaking coming from the hallway; finding no-one there, Pavel returns to his room – and something attacks him… The next morning, the Doctor uses the TARDIS to help Bill move her things out of her foster mother’s flat. Bill tries to stop her tutor taking her boxes into the house, but the Doctor is intrigued by the creaking property, and insists on accompanying his student inside. Clearly embarrassed, Bill introduces the Doctor as her grandfather, and then insists he leave. Paul helps Bill carry her possessions upstairs, commenting how Pavel has hidden himself away with his music, which can still be heard playing inside his room. Bill starts unpacking in her new room, and hangs her late mother’s photograph on the wooden panelling behind her bed; the wood creaks ominously and Bill gets spooked – turning away, she fails to see the picture move… As the storm continues into the night, the housemates convene in the living room. Felicity’s complaints about the lack of phone signal are interrupted when everyone hears a banging coming from the kitchen; sticking together, they follow the noise to a cupboard – and find the Doctor inside, busily checking out the house. Citing the lack of any modern fixtures and fittings, the Doctor tries warning the students away, but halts at the sudden appearance of the Landlord. When the strange man asks if everything is satisfactory he receives a barrage of requests from his new tenants; promising to do what he can, the Landlord reminds them to keep out of the tower, avoids the Doctor’s questions and then taps a tuning fork against the wooden wall panelling, before leaving without a trace. Hearing a loud scratching noise coming from inside the walls, the Doctor insists on staying the night; he encourages everyone to stay up and listen to music on Bill’s phone, but while Felicity and Harry are happy to party downstairs, Bill is angry, not just at being outed as a Little Mix fan, but because she wants to keep this part of her life separate from her tutor. The Doctor still refuses to leave, and wonders about Pavel… Paul, Bill and Shireen go upstairs to their rooms, Paul teasing the girls about their apprehension at the sound of the creaking floorboards. Soon after Paul enters his room he starts screaming; although Bill and Shireen find the door locked they do get a response to their knocking – which is then heard from everywhere around them, as every door opens and closes on its own. Bill and Shireen turn and flee… Downstairs, the Doctor, Harry and Felicity discover that the front door is literally sealed shut. When the window shutters begin closing by themselves, Felicity panics, and manages to get out of the kitchen window before the shutter can seal itself. Outside, the terrified girl tries calling the police on her mobile, but is attacked by something that emerges from a nearby tree… Reaching Pavel’s room in the attic, Bill and Shireen find a record player stuck in a loop – and Pavel still alive, but somehow merged into the wooden wall-panelling. The Landlord reappears and stops the record, causing the wall to finish absorbing Pavel. Explaining how the boy has been preserved inside the fabric of the house forever, the Landlord taps the wall with his tuning fork; a terrible scratching noise begins, sending Bill and Shireen running down the hall. Reaching a bookcase, Bill finds a book that triggers a secret doorway, revealing a flight of stone steps leading up to the tower… Hypothesising that the building is infested by wood nymphs, tree sprites or dryads the Doctor shouts at the kitchen wall to provoke the house; he is successful, and he and Harry watch as a large woodlouse crawls through the very wood. As the Doctor tries to capture the insect a swarm of lice crawls through the door, chasing the Time Lord and Harry into the kitchen cupboard; luckily the cupboard is a lift, allowing the Doctor and Harry to escape into the cellar. At the top of the tower, Bill and Shireen find a bedroom furnished in wood; from behind a wooden room divider comes a girl’s voice… The Doctor and Harry discover boxes of people’s possessions, and a number of lease agreements, dated 1997, 1977 and 1957 – the ‘dryads’ are claiming their victims every twenty years. The Landlord reappears and reveals his reasons for helping the infestation: the creatures saved his daughter. Harry bolts upstairs, but his foot is trap by the wooden steps; as the boy struggles to free himself the Landlord summons the woodlice with his tuning fork, and Harry is consumed by the insects. The woodlice close in on the Doctor, but he offers to help the Landlord… In the tower, Bill and Shireen meet the Landlord’s daughter Eliza, now a creature made of living wood. Shireen stamps on a woodlouse, and is immediately devoured by a swarm of the creatures, her death causing Eliza to grow stronger. The Doctor arrives with the Landlord, and tells Bill how the Landlord found the woodlice in the garden, curled up into little wooden balls, and brought them to show Eliza as she lay terribly ill in bed; that night, Eliza’s music box activated the creatures, who saved her by turning her into wood. When Bill points out that Eliza is seventy years old, the Doctor realises that the Landlord is not Eliza’s father, he is her son, who has been looking after her since he was a child. In tears, the Landlord begs forgiveness from his mother, for finding a way to save her after he saw how the woodlice had transformed her arm into wood. As her fragmented memory starts to return, Eliza becomes horrified that her preservation came from the death of so many children. Furious, the Landlord activates his tuning fork and a swarm of lice flow through the wooden floorboards, ready to kill the Doctor and Bill. The Doctor implores Eliza to stop the creatures, by reasserting herself as the parent in charge. Ignoring her son’s pleas to kill the Doctor and Bill, Eliza takes control of the lice; then, heeding the Doctor’s advice to stop hiding, she opens the wooden shutters to see the night sky, lit up by fireworks from a Freshers party in the park. Eliza tells her son to leave her and see the world, but the Landlord refuses, still wanting to destroy the Doctor and Bill. Comforting her distraught son in her arms, Eliza orders the woodlice to devour them both; in their place appears Shireen, restored to life by the repentant Eliza. As the house starts to make a terrible creaking noise, the Doctor, Bill and Shireen race downstairs, where they find Paul and Pavel restored to life. Racing outside, they rejoin Felicity and Harry, just as the entire building is destroyed by its infestation… Later that night, the Doctor visits the university cellar, where Nardole is busy checking the Vault. Giving his assistant the night off, the Doctor listens as the Vault‘s occupant begins playing the piano he recently provided. Promising a Mexican takeaway for dinner and a story about a haunted house, the Doctor opens the Vault door…

Peter Capaldi (The Doctor), Pearl Mackie (Bill Potts), Matt Lucas (Nardole), David Suchet (The Landlord), Mariah Gale (Eliza), Mandeep Dhillon (Shireen), Colin Ryan (Harry), Ben Presley (Paul), Alice Hewkin (Felicity), Bart Suavek (Pavel), Sam Benjamin (Estate Agent), Tate Pitchie-Cooper (Young Landlord)

Directed by Bill Anderson
Produced by Nikki Wilson
Executive Producers Steven Moffat and Brian Minchin
A BBC Wales production

TX (BBC 1 & BBC 1 HD):
6th May 2007 @ 7.20 pm

*Featuring the Twelfth Doctor, Bill and Nardole

*This episode was made available on the BBC iPlayer with a special binaural soundtrack immediately after it was broadcast on BBC 1. The binaural edition creates a 3D surround soundscape for anyone wearing headphones, placing the audience at the heart of the action while the bumps, scrapes, shrieks and screams echo around them as if they were actually there. To create the enhanced version, the team used new software developed by BBC Research & Development to artificially mimic the subtle effect the shape of the viewer’s head and ears have on what they hear. This lets sound engineers give the impression of specific sounds like the creaks and groans of the old house in 'Knock Knock' being in front, behind, or all around viewers.