I don’t like “Knock Knock” much.
I think it’s obvious if you’ve followed the coverage of last series on this blog – it was my least favourite episode of 2018, and I might go as far as calling it the nadir of the Capaldi era (it’s that or the Whithouse Lake two-parter, really). The general reasons for that dislike are pretty simple: it’s a boring piece of work that conceptually does nothing that hasn’t been done much better before, and sells itself on scares while utterly forgetting to be scary. But, the more I think back on it, the more I’m convinced there is actually more to it – or rather, something lacking at a deeper level. So, let’s investigate.
A good place to start this search, as often with Who, is with El Sandifer, and her review of the episode.
“ …because the culprit in Knock Knock’s abject blandness is pretty obvious: this is 100% down to the malign influence of Blink. And not just in the sense that it’s literally the same house, but in the fact that it’s a house in the first place. Once upon a time, when Doctor Who wanted to be scary it would, you know, do some scary stuff. Monsters stalking the Blitz. Weird Satanic horror on an alien world. Evil tourist busses. Or, frankly, any number of scary ideas from the classic series, only a handful of which were ever “haunted house.” (1)
She is right in identifying Knock Knock as a part of this recent trend in Who history – which then asks the question of why exactly it fails. Why does “Blink”, with what is essentially the same base ingredients, or “Hide”, succeed, while this fails? It all comes down, in the end, to how exactly you define a haunted house, as a storytelling construct and a sub-genre of fiction.