DIABOLIC Trailer Unleashes FLDS Religious Horror Ahead of February Release

A woman returns to the faith she escaped—and awakens something far more dangerous. (Brainstorm Media)

Brainstorm Media has unveiled the official trailer and poster for Diabolic, a stark and unsettling religious horror film set within the closed world of a fundamentalist compound. Directed by Daniel J. Phillips, the film will arrive in select theaters and on demand February 20, positioning itself as one of the more provocative genre releases to kick off the early-year slate.

At its core, Diabolic follows a woman forced to return to the FLDS-style religious community where she was raised after becoming haunted by the vengeful spirit of a cursed witch. What begins as a search for healing quickly mutates into a confrontation with belief systems, generational trauma, and the terrifying power of superstition when it is allowed to fester unchecked. The trailer leans heavily into atmosphere and dread, favoring slow-building unease over jump scares, with imagery that feels both ritualistic and deeply oppressive.

The film stars Elizabeth Cullen (Elvis) in the central role, supported by John Harlan Kim (The Little Things) and Mia Challis (Outer Banks). Together, the cast grounds the supernatural horror in emotional realism, allowing the film’s exploration of faith, fear, and control to land with added weight. Additional cast members include Robin Goldsworthy and Genevieve Mooy.

Phillips co-wrote the screenplay alongside Mike Harding and Ticia Madsen, crafting a story that blends folk horror, religious extremism, and psychological terror. The result, at least judging from the footage, carries an aesthetic and tonal confidence that recalls prestige horror television—there are strong Ryan Murphy–esque vibes here—but filtered through something colder, harsher, and undeniably diabolical.

Produced by Grant Hardie, Vasili Papanicolou, Mark Patterson, Daniel J. Phillips, and Silvio Salom, Diabolic looks poised to tap into a growing appetite for horror that interrogates belief systems rather than simply exploiting them. It’s not just about the presence of a witch’s spirit—it’s about what happens when fear is institutionalized and devotion becomes a weapon.

With its FLDS-inspired setting, ominous spiritual mythology, and commitment to slow-burn terror, Diabolic feels tailor-made for audiences drawn to religious horror that cuts deeper than surface-level shocks. Whether it ultimately delivers on that promise will be revealed when the film opens February 20, but the trailer alone suggests this is one worth keeping on your radar.

Check out the official trailer and poster now, and let us know if Diabolic has worked its way under your skin.