Jeff Light’s review published on Letterboxd:
A bit heavier than I had planned on for a Halloween watch, Hereditary works best as a family drama, though the horror elements are well-considered, too.
I do love me a tight script. Even better when the director's attention to detail is on point from the very start. Seeming lens flares in the camera, signs written in plain view but off to the side, pictures and videos in the background that foreshadow the plot, and snippets of dialogue that explain clearly what's happening. Of course, the audience doesn't know what the significance of any of this is at the start, so it's up to us to note these and remember them for when the pieces come together later in the film. I've only seen it once, and it all seemed subtle enough, but I'll bet it's almost glaringly obvious on a rewatch. I'm down with that though, I LIKE deeply-textured films. Far better than the typical Horror film that relies on an audience accepting genre tropes to explain the characters' actions.
And to complement that writing is the characters and their actors. Byrne's accent slips a time or two, but he's otherwise fine here, as is Shapiro. All I heard about this film was about Collette's performance, and she sure does act A LOT. The story does give justification to go big, but I'm not quite sure it needed to be that big that often. I'll sit on it. For me though, the really great performance was Alex Wolff, who has to cover so much more ground. Whereas Collette's "Annie" is pretty much coming undone from the start of the film with a fairly cringey eulogy scene, Wolff's "Peter" has to go from disaffected stoner to struggling teen to scared kid to much more. He's imminently believable at all times, and he and Collette are key to selling the gripping and heart-wrenching family meditation on grief that Ari Aster constructs here.
I know people who thought Collette was overacting, but I'll save that criticism and focus on the reason why. The film wants us to debate what the easier explanation is in this and many other horror films: is crazy shit really happening or is it more likely that someone is going crazy? And from now on I'd recommend just watching the film because I have to get into SPOILERS to continue...
The film lays down enough background at the start to give you the idea that mental illness runs in the family. Though the big clue is when they mention "D.I.D.", dissociative identity disorder. This is a broader label but essentially it encompasses what used to be called "multiple personality disorder". If you caught that, plus the other hints, there's plenty here to suspect that Annie has been a little crazy for a long time and is now fully losing her shit. It does run in the family after all, and her daughter seems to be Not Right as well. (I looked it up and see that actually Milly Shapiro has Cleidocranial dysostosis, which is classified as a birth defect but is purely physical, with no apparent mental effects.) While the kids don't necessarily know the whole family history, Annie and her husband Steve sure do, and it strained my credibility that neither of them sought professional psychiatric help no matter how obviously poorly the whole family was handling these traumatic events.
& The Ugly:
The final 1/5 of the film finally succumbs to horror movie tropes and looser writing by just leaning on the supernatural to explain a lot. Peter calls for mom instead of calling the cops. He runs up the stairs instead of out the front door. The parents don't just TALK ABOUT IT and work as a team. And what's the explanation for who the book burned? Hmm...the cult? What's the explanation for how all that stuff got done in the attic when the parents don't leave to go to work and nobody heard anything? Umm...spirits? How does Annie just start flying around at the end? Ummm...demon powers? There's even a hint that Charlie's decapitation was part of a plan, which would include so many unplannable variables that the whole thing falls apart if you think about it. Essentially, the end of the film goes full-tilt crazy and you just have to be invested enough to accept it at face value. Similarly to Ben Wheatley's "Kill List", the cult can do whatever it does apparently because... well, because we see it happen, so whatever they did: worked!
Don't get me wrong, I appreciated Hereditary and it's a solid cut above 95% of Horror films that get churned out every year. But it wasn't the horror that did it for me. The real horror of the film isn't that cults may be controlling your destiny, it's that you can't plan for the horrible things that you yourself may help to bring on yourself. Whether it's accidentally hurting those you love or imploding your own career, studies, or mental health, the fact is that we're often not equipped to handle life's curveballs very well. That inability to cope is the truly lingering terror of the film.