Sundance Film Festival 2026 – Undertone is quintessential A24, elevated horror that pays off. Writer-director Ian Tuason’s intimate and effective horror film tells an emotionally resonant story effectively and elegantly. Evy (Nina Kiri) and her friend Jutsin (Adam DiMarco) produce a podcast that explores the paranormal. The podcasters are sent an anonymous email with 10 separate sound files that eventually threaten to unleash a profound evil that threatens their very lives. It seems like a simple even common set up. But Tuason understands horror, and more importantly, the emotions that drive it. By the time Undertone has you under its control you are mentally and emotionally captive. The result is easily one of the most terrifying films in years.
Producing a podcast isn’t easy. Especially when real life gets in the way. In the case of Evy, she has returned h0me to act as caregiver for her dying Mama (Michèle Duquet). No matter. Evy takes care of her mother around the clock and sets up a recording suite in the dining room downstairs. There isn’t much to do but keep her catatonic mother comfortable. Still, even though there is very little physical exertion, Tuason takes care to convey the grueling mental and emotional strain that Evy endures. Nearly every waking minute is tinged with a vigilance and guilt for not doing enough.
After getting settled, Evy hops online to record remotely with her co-host to find that he has a special surprise for her. Justin explains that he received an anonymous email that had 10 sound files that are said to contain creepy demonic elements. The recordings seem to be of a young couple that just found out they are expecting. The pair act as a sort of X-files duo with Justin being the believer and Evy being the skeptic. The camera stays on Evy as we listen to a couple getting ready for bed, then skipping ahead a few hours, we hear the wife begin talking in her sleep. Co-host Justin thinks he hears the wife singing songs like ‘Bah, Bah, Black Sheep ‘and this leads the podcast duo to explore the macabre origins of such nursery rhymes.
Over the next few days the duo continues listening to the files and they get progressively eerie. Then strange things begin to happen in Evy’s Mother’s home. Faucets turn on, strange noises come from unseen corners, and worse, Evy’s mother seems to be wandering from her bed. The plot thickens as the mystery gets more layered and better still, more demonic. As the silence of the large house surrounds her in the late hours of the night, Evy’s headphones funnel audio nightmare fuel to her ears and she can’t be the skeptic anymore.
What makes Undertone not just work, but rise above other similar movies is the focus on what will really heighten the tension. Emotion, setting, sound, and one strong actor are the keys here in luring the audience into its world. That is of course not to mention Kiri phenomela performance as Evy. She is for the most part, the only person on screen. Through her we see the anguish, the stress, and the utter horror of what she is experiencing. If she doesn’t sell it, we as the audience wouldn’t buy it. Tuason’s script is a relentless creation of rising tension while his direction matches it with surprising visual interest and composition. Still, it is the sound that makes this movie what it is. Sound designer David Gertsman delivers Oscar-caliber sounds design that creates another world that we see with our ears. The horrors lie beyond what we can see into what we are forced to imagine.
To compare this to other elevated horror films, I would say that it never reaches the savage levels of terror that Hereditary delivered. In fact, I can’t even remember a single drop of blood on screen. Undertone is more sophisticated with its scares. This is an elegant horror thriller that is likely to have massive appeal for it’s strong story, and lack of grisly visuals. Ignoring the very minor notes I have regarding a clear timeline, everything comes together and delivers.
Undertone is a nerve-shredding thrill ride that worth a listen. An accomplished horror film from Ian Tuason who proves himself capable not just capable of horror, but solid filmmaking too.
