Undertone Summary and Review

Undertone is a supernatural psychological horror film that centres on Evy, a young woman with a troubled past, now living back at home and caring for her terminally ill mother. To cope with the isolation, she co-hosts the titular podcast with Justin, a London-based collaborator we never see: Evy plays the sceptic, Justin the believer, as they dissect urban legends and creepypasta stories.

A Strange Email with a Cryptic Message

The film opens as they prepare to record a new episode. Justin reveals he has received a strange email containing a cryptic message and a set of audio files - files he unwisely opens. After sampling one, he saves the rest for the recording, allowing both hosts to experience them in real time. What begins as natural curiosity soon develops into something far more sinister.

The audio narrative starts innocently enough: a man records his partner while she sleeps because she doesn’t believe she talks in her sleep. But as the content unfolds, increasingly disturbing events on the audio begin to mirror those in Evy’s world. The purpose of the files becomes clear as the pair’s investigation triggers events that unleash something ancient and malevolent with a very specific target in mind.

The Audio and Sound Design Excels

At the core of Undertone is its audio and sound design, and this is where the film truly excels. No effort has been spared in creating an atmospheric soundscape that shapes the narrative and draws the viewer into Evy’s confined world. As the film progresses, we become hyper‑aware of every sound and begin investing each one with meaning. The backwards nursery rhymes are particularly unnerving, transforming otherwise innocent childhood songs into something deeply unsettling.

Despite this strong premise, it often feels as though the writer began with the intention of creating a slow‑burn horror rather than allowing the story to evolve naturally into one. Every sound is carefully designed to create dread and suggest unseen danger, and in that respect the film cannot be faulted. However, it fails to fully capitalise on this unsettling concept, moving at a glacial pace that tests the viewer’s patience more than it builds tension. While the sound design captures attention early on, the film doesn’t do enough with it, leaving long stretches where very little happens.

Visually, there is much to admire. The single location (Ian Tuason’s parents’ house) has the feel of a well‑loved family home, adding authenticity to the setting. The camera work makes effective use of angles and off‑centre framing to emphasise Evy’s isolation. However, the slow camera panning, while often making you hold your breath in anticipation, usually leads to little more than the viewer straining to glimpse something hidden in the shadows. I wasn’t looking for contrived jump scares, but Tuason could have made better use of this to keep the viewer on edge.

Underdeveloped Elements

There are also underdeveloped elements that raise more questions than they answer. Evy’s emotional turmoil is hinted at, but its influence on the present narrative feels diluted and what this means for her choices is left unexplored. Similarly, her mother’s presence, while acting as a vehicle for Evy’s sense of filial guilt, contributes little to the film’s momentum or to our understanding of Evy’s internal conflict. Keeping these details light to avoid bogging the film down in backstory only works when the narrative momentum is strong enough to hold your attention and prevent you from noticing the gaps.

Undertone creates a genuinely eerie atmosphere but, unfortunately, offers little pay‑off. The film’s central ideas are compelling but rarely reach their full potential. The podcast framing concept is welcome, but the gradual reveals fail to escalate tension, never truly igniting the spark of fear that should build to a pinnacle of terror by the end. For a masterclass in how slow‑burn horror can maintain tension while delivering a satisfying payoff, The Night House (review here: The Night House Review) is well worth a watch.

Rating: ★★⯨☆☆

Character & Production Details

Evy: Nina Kiri
Justin (voice): Adam DiMarco
Evy’s Mother: Michèle Duquet
Jessa (voice): Keana Lyn Bastidas
Mike (voice): Jeff Yung
Abby (voice): Sarah Beaudin
Dr. Ram (voice): Brian Quintero

Writer: Ian Tuason
Director: Ian Tuason
Year of Release: 2026
Runtime: 94 minutes