Doctor Who – Series 10 Ep. 4 – “Knock Knock”

Knock Knock
Ah, the creepy haunted house. A classic supernatural setting! When Bill and some other students move into a large mansion for a low price, it seems like a killer deal. And it is, literally. In one of the most squeamish episodes of Doctor Who, it’s up to The Doctor to figure what’s living in the walls.

We start off with Bill and five other students looking for a place to live. After a funny sequence with several undesirable apartments, the crew runs into an old man who takes them to the mansion. The rooms are huge and the rent is cheap. Sure, it’s a bit creaking and the old man is weird, but it looks like a good deal. The Doctor, who Bill says is his granddad, is suspicious, of course.
And for good reason. As they settle in for the night, a couple of students die screaming in their rooms. Knocks and scratches and creaks vibrate out from all corners of the house. Then the doors and windows to the outside all disappear. Luckily, The Doctor had already snuck in. So what’s living inside the walls, causing all this ruckus? Alien insects. Lots of them. When released with specific frequencies, they swarm over the students one by one, dragging them into the surfaces of the house. These are some of the most skin-crawling scenes in the show’s history.
As The Doctor discovers that this has happened before in 20-year intervals, Bill makes her way to the forbidden tower. She finds Eliza, a wooden person living in isolation who is sustained by the bugs. While she says she is the landlord’s daughter, Bill quickly figures out that the math doesn’t work. And that’s the great twist. The landlord isn’t an alien or anything like that. He’s Eliza’s son, who brought the insects to her when he was a child. When he found out they saved her life from an illness, he kept at it, feeding the insects with tenants to keep her alive. But it is a shadow of an existence for Eliza, where most of her memories have faded. Once The Doctor explains what has happened, she controls the insects and ends it. She sacrifices both herself and her son, collapsing the house around them. But she also restores Bill’s roommates.
Besides the great twist at the end, “Knock Knock” is elevated by its unique setting and the power of the support cast. The house itself feels like a character, especially before the insects crawl out. Its creaks and moans, combined with its outdated utilities and dusty regalia, make it a fantastic location. Even with limited on-screen time, Bill’s roommates all feel like real characters, rather than red shirts. David Suchet, who portrayed Hercule Poirot, does a wonderful job as the landlord. He moves from awkward to creepy to sinister to heartbroken. Each act brings another layer to what could have been a standard villain.
To end, The Doctor checks in on the mysterious vault, who’s occupant is playing a Beethoven on a piano. At first, he or she doesn’t seem interested in having dinner with The Doctor. But when he mentions that his latest adventure featured young people being eaten, this person start playing “Pop Goes The Weasel.” Who could mix elegance and psychosis like that? My guess? It’s Missy!
Assorted Thoughts:
– Nice throwback reference to Harriet Jones when Doctor quizzes the landlord on past Prime Ministers.
– The Doctor once filled in for Quincy Jones. Can we see that episode please?!
– One of the eaten tenants from 1977 had good taste in music. David Bowie’s “Heroes/V-2 Schneider” 7-inch single is among their belongings.
– Nardole has a good point. While off-world trips are full of dangers, there are as many things that want to kill them on Earth!
– Next week, zombies in space!