When it was still doing the festival circuit, I listed Undertone as one of the best horror movies coming out of Fantasia 2025. I described it as being like experiencing Paranormal Activity if it was in audio format, so it delighted but didn’t surprise me that during the run, director Ian Tuason was grabbed to helm the eighth installment. Now with a shiny new title card from A24, fresh voice acting (hello, Adam DiMarco), a tightened title (“drop the ‘the’”), and a tenser edit (from Sonny Atkins), Undertone is ready to terrify a larger audience with its punishing audio track.

Evy (Nina Kiri) and Justin (DiMarco) are a pair of podcast hosts who squeeze recordings into their challenging schedules. Justin is recording from the UK and Evy is marooned to her childhood home to provide support for her mother’s palliative care, so the duo records their spooky show at 3:00am her time. Typically playing off each other as the skeptic-versus-the-believer exploring supernatural true crime phenomena, the two enter strange new territory when they live record their reactions to ten audio clips sent to the show via cryptic email. The clips start off like the early moments in the aforementioned Paranormal Activity, with audio of Mike (Jeff Yung) recording his partner, Jessa (Keana Lyn Bastidas) talking in her sleep, but things escalate when Jessa starts singing haunting kid’s songs in reverse. The duo does their best to plow through the remaining audio to cobble together a compelling episode, but they’re often interrupted by a need for sleep, an urgent call, or a bump in the night.

Evy has mostly protected herself from fear with her skepticism, but that changes when she finds herself connecting more and more to the audio. As references to the demon Abyzou ramp up, Evy considers if she is the next target for a malevolent force whose screams seem to transcend her plane.

Again, Undertone lives and dies by its audio, the entire movie taking place in a single location with Evy’s headphones as a gateway between worlds. Every crunch of cereal, whistle of a kettle, or tick of a clock is an anti-ASMR stab in the ear creating a persistent sense of unease. The audio is invasive, taking up space in Evy’s home, asking the audience to consider what might have taken place just over her shoulder. Tuason and his DOP, Graham Beasley, went to the Mike Flanagan and Leigh Whannel school of weaponizing negative space and they use empty corners of Evy’s house to ask the audience to use their imaginations and the audio to fill in haunts. Shots of Evy’s back leave her looking so vulnerable to the tin cans placed atop her ears. The only faces we ever truly see are Evy’s and her mother’s, forcing us into her same isolation. Evy might leave the house, but the camera doesn’t and paired with toggling shots between Evy or the entity’s POV, it makes the entire experience claustrophobic forcing the audience to fester in dreadful seclusion.

Undertone is sometimes a grab bag of horror hits, taking its concept of an audio track as a conduit and decorating it with religious iconography, haunted songs and myths, and even a fugue state crayon scratch of something scary. But with that, its guerilla Canadian horror filmmaking at its finest; a liminal horror feature put together by scrappy bubbling creatives. The set is the director’s house, the audio clips were recorded before principal photography, and death rattles and in-world phone calls were recorded by sound guys into iPhones. Something that started with everyone on set placing objects in frame then hiding to add scares to long shots turned into an entire theater reacting to a mirror scare like the audience gasping at the wall climber in Hereditary.

Undertone is a refreshing flip on screen life that uses phone calls and audio clips to bring a large story into the small room of a target protagonist. Is it a lesson in catholic guilt for a skeptic who’s been avoiding her mother’s religious zeal? Perhaps. But above all, it’s a tight and contained terror that will leave audiences trying to find a way to use their blanket to cover their ears.

Undertone hists theaters March 13, 2026