I really enjoyed Ole Bornedal’s The Possession partially because he seems to recognize that you don’t need a gazillion dollars to craft an effective horror movie – as if The Blair Witch Project (1999) didn’t already make that abundantly clear, especially when you take into account that The Possession, at $14 million, is budget-wise closer to something like Avatar – and that the best horror revolves around characters you give a damn about.
In other words, the more you care about the people involved, the less you have to invest in jump scares and what not because it has the opposite intended effect and distracts from the character drama.
In fact, the weakest parts of the movie, relatively speaking, are the more effects-heavy sections (such as when the demon is revealed. It’s not that it’s bad more than it’s something you’ve seen done better in movies like Poltergeist II: The Other Side (1986), The Unholy (1988) and even The Manitou (1978), which I’m hoping someone remakes because it’s too awesome not to.
Besides, I’ve seen movies like Avengers: Infinity War (2018) and recognize that if smaller budgeted movies are going to make their mark, unless the effects are remarkably innovative, like in The Thing (1982) or Society (1989), they shouldn’t because they can’t complete.
The Possession revolves around a family plagued by a dybbuk box, which according to Jewish mythology is used to hold a demon in thrall.
It’s purchased by Clyde (Jeffrey Dean Morgan) who fairly obviously didn’t know of such things till it began to possess his daughter (the movie revolves around his attempt – once he understands what happening, which happens way too easily for my liking – to free her from the demon before it possesses her) who already has enough to deal with his marriage coming apart around him, never mind a demon with the predilection to possessing children.
The movie doesn’t get bogged down in the minutiae of the possession (which is good because it’s sort of absurd) and instead spends the bulk of it’s time building atmosphere and helping us connect to the characters.
It works really well. Surprisingly well in fact because it end up being genuinely creepy at times, which is saying something.
And I should mention that dybbuk boxes are a thing – or at least people believe them to be – because if you go to eBay you can find numerous examples offered for sale.

And while I’m an agnostic I also recognize that there’re things beyond my comprehension, so I’d prefer not to poke the bear, so to speak.