J. J. Wright’s review published on Letterboxd:
Had the makings of a potential all-timer before the final act showed some strain and changed tactics in a way I didn't quite go for (but which, in fairness, is completely telegraphed and expected). Stretching beyond its means aside, that sort of telegraphing/obviousness is the film's only other major flaw. Otherwise it establishes a concise visual language and Radek Ladczuk renders its world in a palette of drained, oppressive blues, charcoal blacks, and sickly pale skin tones.
Kent does great work creating up a knife's-edge tension, both through her direction of young Noah Wiseman (who she makes alternately THE MOST ANNOYING CHILD EVER and sweet to the point of being pitiable) and her skill at creating a sleep-deprived, grief-haunted tone. Essie Davis, for her part, is game for whatever the film throws her way and shows an admirably broad range in the process.
The film is quite effective, early on, as an exaggerated look at the powerful love/hate dynamic of child rearing and motherhood, a dynamic that's just not talked about enough. And though the thematic material related to trauma, grief, and inner darkness is hammered home pretty hard, that doesn't stop the film from being both creepy AND psychologically upsetting. The fingernail marks on my thighs could speak to that.
I can somewhat forgive it its final act issues based on the strength of what came before, subtlety be damned. And I also have to give it great credit for the strength of its images, for their composition and framing and for the dreamy way it moves on. In that sense, much like the better Under The Skin, its power as a piece of cinema to be experienced is far greater than its power as a specific story.