I was surprised recently to discover that I hold what might be a contrarian interpretation of this movie. I think all of the supernatural elements in the movie are delusions, and none of them are "real." While there's enough ambiguity that you could reasonably disagree, I think that the mom and son are unreliable narrators as a result of their shared mental illness and grief.
The twist is that the cult is completely real. And it was created by the grandmother, who had the same illness as the mother and son, but who convinced others to believe her delusions. And now there's a weird cycle where the cult is helping to manifest similar delusions in the next generation. The grandmother is haunting them, but through her genes and through her legacy, not as a ghost.
So when there's a deer in the road, or naked people in the attic, that's the cult, and that's real. And part of the way this family is being tortured is, yes, they are unwell, but they really are being preyed upon in this horrifying way. And this makes it impossible for them to know what is real.
A useful character to pay attention to is the dad. He's outside the family tree. He has an accent, just to emphasize his outsider status. And he's a good litmus test for what is real. He takes the phone call about the grandmother's body being moved, so that really happens.
I think the son's weed use is another clue. Weed can induce psychosis in people like him with certain predispositions.
When I shared this theory recently, I was told that this interpretation is as unsatisfying as if it had all been a dream. I disagree. All of the meaningful events still happen, just not in the way that we see. To pick one example, I think it's more meaningful that the mom is the one to light the dad on fire than some demon.
Again, if you asked me to prove the supernatural elements aren't real, I couldn't definitively. But I think the movie is just so much more effective through that interpretation in terms of exploring ideas around heredity.
What are your thoughts?
Edit: Lots of great responses. I enjoyed this one from u/Tough_Grape8094.
>I think you're picking up the central metaphor of the movie, but why not just allow it to be a metaphor. Like, in this world, Demons can exist, and supernatural forces can alter the way we interact with the world around us. Through that world, though, Aster is exploring themes of inherited mental illness, misplaced anger, and complicated feelings of grief. While looking through that mindset (that everything works both on the literal level, and as a metaphor), Byrne's character's death has way more impact. It's scary and mind bending in a literal level. But in a metaphorical level, it's showing a woman's attempted self destruction (remember, she's burning the book, expecting to be burned up herself) end up destroying the man she loves. She doesn't have to literally put kerosene on him and light the match for the same themes to be explored. Plus, we empathize with her more, knowing it was a mistake within the narrative.
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