The Harrowing

The Harrowing is the sixth and final episode of the first season of Inside No. 9.

Plot
Katy Hepworth, a school girl in her full uniform including dark tights, has been hired to take care of Hector and Tabitha's mansion while the two go out for the evening. They usually never leave the house, but have a rare event to attend that evening. Tabitha greets Katy at the door and explains that the house is always kept at −3 °C as Hector and Tabitha's disabled brother, Andras, needs the air to be at this temperature. Katy has brought along a thick coat due to this. The paintings on the house's walls depict the Harrowing of Hell. After meeting Hector, Katy is disturbed by Tabitha's descriptions of Andras, who, it is claimed, does not have a mouth. He instead keeps a bell, which he never uses, beside his bed. Katy is informed not to go upstairs.

Hector and Tabitha leave and Katy is spooked by the house, especially when she finds a stuffed cat on the sofa. She sees an old photograph of Hector, Tabitha and Andras as children, but Andras does not look disabled. Katy's friend Shell arrives also in her school uniform and tights and plays with Hector's stairlift, sending it upstairs. Katy warns Shell not to break anything as she was told, and is startled to see the now-live cat. Katy tries to call her father so she can leave, but the house has no mobile phone reception and the house phone's party line is tied up. As she prepares to leave, the stairlift returns downstairs and Andras's bell rings. Katy is scared of going upstairs, but, at Shell's insistence, the two go to check on him.

Katy and Shell explore and enter Hector's bedroom, where they find a circle of salt around the bed. They hear the bell again and trace the sound to Andras's room. When Katy opens the bed's curtains, Andras's deformed body is revealed: he is tied to the bed and gagged. Katy attempts to untie him, believing that Hector and Tabitha have kept him prisoner. Shell wonders how Andras could have rung the bell if his hands were tied. Hector and Tabitha appear and show that it is they who rang the bell. They quote Dante's Inferno and explain that Hell is cold, as the text says, so the house must be kept refrigerated for Andras. They say he was possessed at age ten by Castiel, demon of mischief, but Castiel needs a new human host every fifty years, and Andras is now dying. Katy has been chosen as the next host after a mutual friend at Tabitha and Hector's church recommended her to them. It is revealed that Shell also attends the church, and she helped them to lure Katy to the house. Shell implies that the church's members protect the earth from being overrun by demons.

Tabitha and Hector prepare to inject Katy with a sedative, but she fights back, managing to taser Tabitha. She runs downstairs only to find that the door is locked. Shell catches up with her and says that Katy cannot escape. Shell says she wanted to be Castiel's new human host, but she is too weak-willed and fat, whereas Katy has the strength of character needed to keep the demon contained. Shell then injects Katy, who collapses with a frightened look. Upstairs, they strip Katy down to her school-standard white bra and classic white knickers and ties her to a chair with cable ties as well as cleave-gagging her, while Shell feeds Andras his last supper: rusks and baby milk, the only food he can manage. Hector, Tabitha and Shell leave Katy to become acquainted with Castiel, who, they say, will possess her as Andras dies. Andras suddenly gets and advances on Katy. As she screams through her cleave gag, Andras repeatedly cries: "Mischief!"