FrightFest 2025 Review: Slasher and Supernatural Don’t Mix Well in WHAT SHE DOESN’T KNOW

High school friends Indy (Siena Agudong) and Jordan (Conor Husting) shun their prom and insulate themselves at the secluded family home of mutual friend Brynn (Jessica Belkin). The trio have a ‘too pretty for prom’ party, which seemingly has two purposes: shun the tradition and pressures of the annual festivities and to avoid the ‘Genesis Killer’, a murderer who has targeted girls at the trio’s school. The killer doesn’t just take lives, they take a victim’s rib as well. Surely staying away from the world is the best thing to do, but closing themselves off physically inadvertently opens up something else.

The Genesis Killer isn’t the only one causing agitation and panic – Indy’s anxiety is compounded by the recent suicide of one of her sister’s, Olivia, and her impending move to college far away from best friend, Brynn, who doesn’t know about her higher education aspirations. Brynn appears to be stuck in a phase of apathy, having lost her mother years before and not knowing where her globe-trotting father is. In the middle is Jordan, the caring figure who tries to address the problems at hand.

When a fresh murder takes place just before the prom, strange events start to unravel: Indy has strange visions of her sister; Jordan uncovers a strange room that glows orange, and Brynn is visited by one of her father’s exes, who gifts her a delightful delectable that is more than frosting and sponge. As the events of the weekend unravel and take shape, the secluded and sprawling safe haven might be the worst place to be. 

What She Doesn’t Know offers a relatively simple premise in a minimalist way – three high school friends holing up in a secluded location to avoid a killer. However, it never really seems to settle. What appears to start off as a slaher ’whodunnit’ seems to lose momentum, and, in order to keep the engine running, a couple of characters are briefly introduced, seemingly to offer up a possible killer and motive, but these characters leave as quickly as they are introduced, usually with no explanation or understanding about why they were there in the first place. 

As more spooky and eerie events take place in the house, What She Doesn’t Know seems to shift to become more of a supernatural thriller. This climaxes with a slasher/supernatural battle that doesn’t quite fit and leaves you with more questions than answers.

The first half of What She Doesn’t Know is well paced and sets up the right level of intrigue and suspense; however, too many variables are introduced, seemingly in a bid to be original and unpredictable. As events generally take place in one location, actors Agudong, Belkin and Husting do very well to carry everything forward and keep momentum going, despite the genre shift. Each of their performances is disciplined and mature.

Both the title and poster – which features Indy underwater in a pool - are vague and evocative, which presents a level of ambiguity – pretty good for a horror film – but this is also its crutch – it doesn’t seem to be too sure of what film it wants to be. Despite the solid performances and interesting premise, What She Doesn’t Know overcomplicates itself with a little too much unnecessary backstory, reliance on red herrings, and trying to utilise too many sub-genres. 

Movie Score: 2.5/5