Horror has always been a genre that thrives on restraint — on what you don’t see, what you almost hear. With Undertone, Canadian writer-director Ian Tuason doesn’t just understand this principle; he weaponizes it. The result is one of the most atmospherically suffocating horror films of the year — a movie that crawls under your skin not through spectacle, but through sound.
The Setup
Evangeline “Evy” Babic (Nina Kiri) is a young woman with a Catholic upbringing, living alone with her comatose mother, for whom she provides round-the-clock care. Together with her friend Justin (Adam DiMarco), she co-hosts The Undertone, a horror podcast where they investigate supernatural occurrences — Evy dismissing them as hoaxes while Justin fully believes. Their dynamic shifts when Justin receives an anonymous email containing a string of letters and ten audio files recorded by a couple named Mike and Jessa, the latter of whom talks in her sleep.
What begins as a quirky podcast investigation slowly curdles into something deeply personal and terrifying. When Evy receives these audio recordings of a young pregnant couple experiencing paranormal noises, she realizes the woman’s story mirrors her own life — and each new recording scratches at her sanity, drawing her into a fate she cannot escape.
A Director Announces Himself
As horror continues to thrive through the 2020s, Tuason drops a terrifying gem. It’s a film that engages with themes dominating the genre lately — grief, loss of faith — but embeds them in a sonic and visual nightmare that announces its filmmaker as a major talent. Where horror directors often cut corners with cheap tricks like jump scares or overcooked music cues, Tuason prioritizes negative space, a constrained POV, canted angles, and simply incredible sound design to lock viewers into the same nightmare as his protagonist. He doesn’t want you to merely watch something unfold — he wants you to feel it as sound and image reach something primally fearful.
The film was, remarkably, shot in Tuason’s own parents’ house — a detail that explains the particular lived-in dread of every corner of that space, where the mother’s impending death hangs in every room like a second presence.
Nina Kiri Carries the Film
Undertone is essentially a one-woman show. We spend its entire runtime locked into Evy’s POV, and it is Nina Kiri who makes that confinement bearable — and at times unbearable. She brings a quiet desperation to Evy, a woman stretched thin between grief, skepticism, and dawning terror. When the supernatural begins to erode her rational defenses, Kiri’s performance never tips into hysteria; instead it simmers, which makes it all the more effective.
When Evy puts on her podcasting headphones, we are similarly locked into a noise-canceling hum, hearing only the podcast and the audio clips they’ve been sent. As Evy and Justin play detective, trying to figure out what’s going on with these supernatural sounds, we join the mystery. It’s an ingeniously intimate device.
The Demonic Heart of It
Playing additional recordings from Mike and Jessa reveals Jessa speaking what at first sounds like gibberish, but when played backwards reveals “come in, Abyzou.” Through research, Evy and Justin learn that Abyzou is a demon in Mediterranean and European folklore said to cause miscarriages and drive mothers to murder their own children out of jealousy, as she herself was infertile. It’s a piece of genuinely chilling mythology, and Tuason weaves it into Evy’s personal circumstances with unsettling precision — giving the supernatural threat an emotional weight beyond mere genre scares.
Where It Stumbles
The film is not without its flaws, and critics are divided. The Rotten Tomatoes consensus calls it a film that “masterfully uses negative space and unsettling audio to build its creeping dread,” erupting as “a diabolically immersive aural nightmare.” But dissenters have a point too.
Benjamin Lee of The Guardian gave the film 2/5 stars, noting it contains elements of Paranormal Activity, Session 9, Hereditary, The Ring, and The Blair Witch Project — “enough sighs of familiarity to give horror fans a scary case of déjà vu.” For genre veterans especially, the film’s DNA is visible in nearly every scene.
Audience scores also reflect a genuine split: CinemaScore audiences gave the film a “C” grade, with only 41% of PostTrak respondents saying they would definitively recommend it. Those seeking propulsive scares or a satisfying climax may leave frustrated — the film leans heavily into ambiguity and mood, and its ending divides viewers sharply.
Sound as Cinema
What ultimately elevates Undertone is its commitment to audio as a cinematic language. Audience members at early Dolby Cinema screenings reported being visibly shaken — some trembling, some in tears — largely due to how the sound experience immerses you in Evy’s waking nightmare. Watching this on a laptop with tinny speakers would be a fundamentally different — and lesser — film.
Empire’s John Nugent awarded it 4/5 stars, writing that while it may trade in somewhat familiar genre tropes, “its form and its function feel fresh, fluent and flippin’ frightening.” That captures it well.
Verdict
Undertone is a slow-burn horror film that rewards patience and punishes those hunting for conventional thrills. It is a debut of remarkable confidence — a film that trusts silence, trusts its lead actress, and trusts that the most terrifying thing in any room is often what you almost hear. It stumbles in its final act and wears its influences openly, but as an exercise in sustained, suffocating dread, very few 2026 horror films have matched it.
Made on a budget of just $500,000, it has already grossed over $20 million — proof that great horror doesn’t need a blockbuster budget. It just needs something to say, and the courage to whisper it.
Best experienced in a darkened theater with premium sound. Bring headphones if you must stream it — and maybe leave the lights on.