An episode set in a gothic mansion owned by a brother and sister who shut themselves away from the outside world.

Inside No. 9 knocks at its darkest door, where brother and sister Hector and Tabitha never go out and have to live in a carefully refrigerated gothic mansion. But tonight they have an event so special that a babysitter is required.

For Katy, the offer of £88 in the hand is too good to turn down. And, what could be so difficult about baby-sitting Andras, Hector and Tabitha's bedridden, disabled, elderly brother, whose bedroom is up on the top floor of the house?