Alice Stoehr’s review published on Letterboxd :
You know the old horror chestnut about how "the call is coming from inside the house"? Well, in The Babadook, the monster is coming from inside the mother/son relationship. It's a storybook ghoul that glides like the witch from The House on Haunted Hill, clad in a top hat and overcoat like some tall Victorian gentleman. It's shudder-inducing, to be sure, as it drifts in and out the house's shadows, but here's what's even scarier: the mutually self-destructive aspects of parenting for which the Babadook is a metaphor. Impressed though I am by writer-director Jennifer Kent's technique, with cutting and framing that consistently amplify the terror, I'm most awed (and deeply upset) by her ideas and the eloquence with which she articulates them throughout the story.
This is, without hyperbole, among the most dead-on movies about depression I've ever experienced. The character of Amelia curled up in bed or sitting up for hours (watching some channel's late-night Méliès marathon, apparently) chilled me far more than any of the things that go bump in the night. Yet scarier was the fact that her and her 6-year-old son's sicknesses feed into one another, because the two of them are interdependent, inhabiting the same airless household. There is love here, but it's hard to separate out from the grief (for a lost husband/father) and resentment that have tainted it. These are abstract and very complex emotional phenomena, yet Kent finds dramatic analogues for them within Amelia's deteriorating social life and infected headspace. The Babadook moves in cycles, descending ever deeper into solipsistic melancholy.
I'm so accustomed to movies about monsters and ghosts playing by roughly the same rules that it's a shock to see those rules inverted here. To see a monster explicitly and intricately represent a character's interior state to the point that the monster's own desires, origins, and persona are immaterial, as is the question of whether it's real or not. These things don't matter—the movie has little intrinsic interest in the Babadook—so they're not addressed, and that speaks to economy of Kent's writing. What does matter, always, is the poisoned space between Amelia and her son Sam, and that's where the film finds its most harrowing "scares." I use scare quotes there because that mere word seems insufficient to describe something like Amelia howling "I AM YOUR MOTHER" at her recalcitrant son. At its darkest, The Babadook goes beyond what I'm used to experiencing in horror movies. It not only uses a clip from Bava's Black Sabbath, but earns the hell out of the comparison.