It was hard for me to settle on a score for the new Argentinian horror film When Evil Lurks. During any given scene, my rating could swing a whole number in either direction from the 3½ Pulses I ultimately gave it. A large part of that back-and-forth is no doubt due to expectations. Completely unwarranted, I for some reason expected When Evil Lurks to be an A24-style slow-burn, a pastoral meditation on psychological terror. When Evil Lurks is still shot gorgeously in that style, but it’s more like an eviler Evil Dead than The VVitch, bleak and unrelenting, daring you to keep your eyes open as it pushes the boundaries of gore and horror with each escalating sequence of brutality.

Everything starts out calm enough as brothers Pedro and Jimmy investigate a series of gunshots heard on the outskirts of their farm at night. When they find the mangled corpse of a stranger in the morning, they soon learn that the body is that of a “cleaner,” or exorcist, on his way to a neighbor’s house, called to properly kill the neighbor’s possessed son. The adult son is what they call “a rotten,” a barely living, bloated behemoth covered with pus-filled boils (I warned you, this movie is disgusting. There’s lots of pus. Lots of oozing.) Since they don’t know how to properly kill a possessed one without freeing the demon inside, the brothers figure the next best thing to do is put him in their truck and dump him as far away as possible. This will only prove to be their first mistake in a series of many, each with a consequence more horrifying than the last.

Writer/director Demián Rugna is as much a craftsman as he is a sadist. Even when nothing terrifying is happening on the screen, the pace of the editing and the subtle sound design produce a suffocating effect. It’s like if Uncut Gems was a French or Korean extreme horror film, only it’s in Spanish with an odd English translation that, whether intentional or not, lends to the on-edge feeling that permeates the film. Similarly, the juxtaposition in the time of day to the vicious nature of the events subverts the expectations of the horror genre. While there are scary night scenes, just as often the movie takes place during the bright light of day, almost as if to deprive you of the comfort of shadows obscuring the viscera, literally shining a light on the macabre mayhem.

So the film is obviously not for everyone. It’s probably not for many. The violence is not only unflinching, but it involves children, animals and self-harm, and there were multiple scenes that tested the limits of this horror fan. But, if the extreme is your thing, it doesn’t get much better. Rugna has constructed a possession film unlike any other. He has created a world with a set of rules only to show the grisly results when his characters break them. There’s no denying his craft, even if you don’t like his infernal machine.