Departing from the typical, tired possession movie formula, Sisters of the Plague is at its core is a strong drama about a dissolving family with a festering horror heart. There are moments of unnerving terror balanced with glimpses of a daughter/father dynamic decaying under the pressure of grief and alcoholism. All of this boils together until the film’s climax, which is as jarring as it is ambiguous. If you’re tired of the same old possession flick, this one’s like an adrenalin shot. And the needle goes in slow.

Co-written by Jason Banker (Toad Road, Felt) and Jorge Torres-Torres (who also directs), Sisters of the Plague is a micro-budget film that banks a lot on its heady ideas and ambitions. But Torres-Torres’ ambitions aren’t constrained by the normal trappings of the genre. He’s made a possession film, sure, but one that transcends and damn near brutalizes the audience with atmosphere.

I can’t even exactly describe what makes the atmosphere so effective in Sisters. It just is. I can say that it’s an unsettling atmosphere and a lot of that has to do with one simple aspect: I had no fucking idea where this film was going. It meanders a bit at the start, then once I got hip to the core story, I still had no idea what direction Torres-Torres was taking me. This, ultimately, made Sisters of the Plague all the more powerful. It’s an absolute gut punch come the third act.

In New Orleans, Jo, as played by Josephine Decker, is a haunted house tour guide. At the start of the film, it’s clear she’s going through some issues. Her father Bob (Thomas Francis Murphy) is an alcoholic, but not the movie version of alcoholics we typically see. Bob is ill, eroding away physically and spiritually with each pull from the bottle. So Jo is dealing with that. Piled on top are the curious circumstances of her mother’s death. Furthermore, she’s beginning to see things and experience wildly disturbing late night visions. They’re like bouts of sleep paralysis on crack. They both live with Jo’s girlfriend Kate (Isolde Chae-Lawrence), who initially seems more disturbed by Jo’s late night freak outs than she is.

To get to the root of these troubling experiences, Jo visits a psychic and gradually gets involved with the occult scene in New Orleans. This whole aspect of psychics and the occult is presented in a very organic way. Not just because they’re in New Orleans, but also because it bleeds into the story in very natural means –with Jo’s participation in a pseudo-scary story club (which I badly want to be a part of).

In Sisters of the Plague, the very notion of possession is no mere invasive demonic condition. It’s a symptom of the grief and uncertainty that cripples Jo. Or is it? The vagueness surrounding her worsening condition is just as discomforting as watching her thrash about on the streets – delivering primal screams and thrashes reminiscent of Isabelle Adjani in Possession. Her performance is center stage.

An accomplished writer and director herself, Josephine Decker here shows natural chops and devotion that add a ridiculous amount of weight to the character of Jo. She’s charismatic as hell, as shown in the scenes with her doing her tour guide thing, but her charisma masks some deep wounds. This is shown during the scenes with Bob, the one person in her life that can hurt her more. Bob is a drunk, like I mentioned, and on screen Thomas Francis Murphy gives a disturbingly real performance. He portrays alcoholism as the actual disease it is, not a quirk to define his character. When he wakes up, his first thought is getting booze in his system. Finding the bottle opener is a massive triumph for him. A triumph that deserves a drink or ten. Alcoholics find rewards anywhere they can.

The secret Bob is keeping in his pickled brain is about the death of Jo’s mother. When she begins to press harder about the answer, things begin to change. The film itself begins to change. It’s a horrible shift to witness (in a good way). Sisters of the Plague is like a virus of grief and anger and possible psychosis all wrapped in an indie horror shell.

My one problem with Torres-Torres’ film is the CGI. It’s subtle and used frugally, but every single CGI shot is unnecessary. The film is so keyed up on organic tension and terror that in the moments where CGI is used, it loses a lot. I get why they used it. To enhance the idea of a possession. But I don’t think it’s needed at all. The film is genuinely effective and scary enough without these subtle touches from a computer.

Fans of Toad Road and Felt will certainly dig Sisters of the Plague. It fits into that category of genre-bending films. Horror without being overt about the tropes. Horror without boundaries. It’s certainly one of the most unique possession film I’ve seen in years. Like the best horror, it makes you question what you’re watching and then gets under your skin. And then corrupts your nerves.

Sisters of the Plague is playing NewFest in NYC this Sunday. Keep your eyes peeled for more screenings down the line.