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‘Diabolic’ Review: Uneven Balance of Religious and Gonzo Horror

Daniel J. Phillips's 'Diabolic' sets its sight on fundamentalist Christian groups but can never quite commit to a subgenre of horror.

Diabolic Elizabeth Cullen

Brainstorm Media

Given the deluge of religious horror over the past few years, you can be forgiven for missing Godless: The Eastfield Exorcism, Nick Kozakis’s exorcism movie that has a lot more to say about religious extremism than the power of the devil. It’s the kind of film that is so good – and so easily overlooked – that you think twice before skipping the next Australian horror film that comes your way. But while Daniel J. Phillips’s Diabolic may have its sights squarely set on deadite-inspired mania, it is no Godless, falling prey to an uneasy mashup of slow burn and silliness that can never quite gain traction.

As a former member of the Fundamentalist Church of Jesus Christ of Latter-Day Saints (FLDS), Elise (Elizabeth Cullen) has more than her fair share of religious trauma. Now living a normal life in the suburbs, there are still vast parts of her upbringing that Elise cannot remember – including a deadly baptism hinted at in the film’s cold open. And when her frequent blackouts begin to get worse, Elise chooses to follow the advice of her therapist and return to her religious community to perform a guided trip with her former elders.

You see, unlike proper Mormonism, the FLDS community never turned its back on the hallucinogens allegedly used by Joseph Smith in the earliest days of the church. So, with the help of her boyfriend Adam (John Kim) and best friend Gwen (Mia Challis), Elise travels to her childhood baptistery for a vision quest guided by Hyrum (Ryan Goldsworthy), a former classmate. 

At first, everything seems to go well, and Hyrum and his mother are even able to draw an unknown substance out of Elise that seems to cure her spiritual ills. But Elise isn’t just tripping; she’s also remembering, and her visions of childhood friend Clara (Luca Asta Sardelis) suggest a forbidden relationship from long, long ago. Meanwhile, lurking around the edges of the baptistery, another figure begins to close in on Elise and her friends. And before the end, this slow-burn religious horror will ratchet up to a spectacle that can only be described as Mormonism's answer to Sam Raimi.

If that premise – a former Mormon who does ayahuasca to remember possessions and queer love – sounds like something from an exploitation film, well, then, I have good (or maybe bad) news for you. Diabolic is a much more restrained movie than you might guess. This is a film where the biggest conflict is the mismatched libido between Adam and Elise – a simmering resentment that bursts out randomly in the middle of the film. For much of the film’s first hour, Elise slowly recovers her memories of a childhood in the FLDS, a remarkable breakthrough that is treated with skepticism or impatience by most of the men around her.

Working in the film’s favor is its small cast, which mostly equates itself well. Cullen is a strong anchor for the movie, running through the standard trauma-to-possession arc of most religious horror films without much reason for audiences to complain. Goldsworthy is also solid as the adolescent friend with a crush, who, in adulthood, has grown into the twisted box he allowed himself as a lovelorn FLDS member. The rest of the cast is less remarkable, but also tasked with serving major plot twists – a betrayal here, a suicide attempt there – that prevent Diabolic from ever truly finding its footing. It may have an outlandish premise, but the execution is solidly by the book, and the film struggles to carve out a space for itself with these two competing ideals.

(It’s worth shouting out Will Spartalis’s score, which combines dissonant tones and vocal harmonies to great effect. It may not carve new musical ground, but it’s the best-developed part of the film, and it gives even Diabolic’s choppiest sequences a sonic grounding.)

But for all its inconsistencies, there is a ten-minute stretch of movie that has wormed its way into my brain. Near the end of the film – before things really begin to take off – there is a scene where Elise crawls underneath the baptistery in search of more clues to her identity. Soon, she begins to hallucinate her adolescent friend, and the two chatter away even as Elise digs desperately into the ground with her bare hands. Once she’s unearthed what she’s afraid of, she collapses, and the camera slowly pulls out from under the ground, pushing her small patch of light into a smaller and smaller corner of the screen.

Up until this point, Phillips’s direction has been unremarkable – competent and self-assured, but lacking a visual or narrative hook to elevate the story beyond its simple trappings. And while the film will no doubt win over some horror fans with its Evil Dead-esque final act, it was this short blast of absurdism and panache that hinted at Diabolic’s true potential. Because the film opens by presenting itself as based on a true story, it may be that Phillips and co-writer Mike Hardin resisted the urge to break their film out of its aesthetical boxes. After all, there isn’t a lot of religious horror that dabbles in gee-shucks line readings or Midwestern charm.

But even setting aside those flashes of potential, what remains in Diabolic is a perfectly fine possession, one whose low budget and clunky scripting are mostly overcome by some smart choices in setting. There are many better horror films than Diabolic, but there are many worse horror films, too, and Phillips and company have crafted something destined to be a late-night discovery on a streaming platform like Tubi or Pluto. And horror fans who do stick through it will at least be treated to one of the best bits of bodily violence this side of Josh Bazell’s novel Beat the Reaper. If you know, you know. [2.5/5]

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