Doctor Who: Season 10, Episode 4

10 - 4: Knock Knock

Bill is moving in with some friends and they've found the perfect house - so what if it's strangely cheap to rent, and the landlord is a little creepy? The wind blows, the floorboards creak, and the Doctor thinks something is very wrong. What lurks in the strange tower at the heart of the building - and why can't they find any way to enter it?