Undertone (2026) Trailer Breakdown & Deep Dive: A24’s Quietest Horror Might Be Its Most Disturbing

There’s loud horror, there’s jump-scare horror—and then there’s silence weaponized as fear. That’s exactly the lane Undertone is carving out with its newly released Official Trailer HD, and honestly? This one doesn’t scream. It listens.

Distributed by A24, Undertone is the kind of horror film that crawls under your skin slowly, patiently, and refuses to leave. Directed and written by debut filmmaker Ian Tuason, the film is set to hit U.S. theaters on March 13, 2026, after premiering at Fantasia in 2025—and the trailer makes one thing crystal clear: this is not a conventional haunted-house story.

A24’s Undertone: Horror You Don’t See—You Hear

At first glance, Undertone looks deceptively simple.

Evy (played by Nina Kiri) is a paranormal podcast host who doesn’t actually believe in the paranormal. Her co-host Justin (Kris Holden-Ried) does. That skeptic-versus-believer dynamic feels familiar—until the film flips the format entirely.

Here’s the bold creative swing: Evy is the only character we ever see on screen.

Everyone else—Justin, her dying mother, strangers, experts, frightened couples—exists only as voices. The horror isn’t framed by what’s happening in front of the camera, but by what’s creeping in through sound design, audio recordings, phone calls, and silences that feel too heavy to ignore.

That’s not a gimmick. That’s confidence.

Trailer Breakdown: What the Undertone Trailer Is Really Saying

The Undertone Official Trailer HD is restrained to the point of discomfort. No rapid cuts. No monster reveals. No overexplaining.

Instead, it leans into:

• Static-filled audio clips

• Unexplained low-frequency sounds

• Pauses that last just a beat too long

• Evy’s face reacting to things we cannot hear clearly

This is a trailer that dares the audience to lean in—and rewards them with unease instead of answers.

The most chilling moments aren’t visual at all. They’re sonic. A muffled knock. A distorted whisper. A noise that doesn’t belong to any known source. The title Undertone suddenly feels less like a name and more like a warning.

Story: Caregiving, Grief, and Psychological Collapse

Beneath the paranormal setup is something far more personal—and far more unsettling.

Evy returns home to care for her dying mother, Mama (voiced by Michèle Duquet). Grief, exhaustion, guilt, and emotional isolation all pile up at once. That’s when Evy receives audio recordings from a married couple experiencing unexplained noises in their home.

As Evy analyzes the tapes, the line between investigation and obsession blurs. The sounds begin to bleed into her daily life. Are they real? Are they imagined? Or is something far worse happening?

The trailer smartly avoids answering any of this. Instead, it asks the most terrifying question of all:

What if the horror isn’t supernatural—but you can’t prove that it isn’t?

A One-Actor Film That Doesn’t Feel Empty

Making a feature-length horror film with only one on-screen character is risky. But Undertone turns that limitation into its greatest strength.

Nina Kiri carries the entire film on her shoulders, and from the trailer alone, her performance feels raw, lived-in, and unsettlingly intimate. There’s no relief valve. No cutaways. No safety net.

The supporting cast—Keana Lyn Bastidas, Sarah Beaudin, Jeff Yung, Brian Quintero, and others—exist purely as voices. And that choice forces the audience to engage differently. You’re not watching horror unfold; you’re participating in it by imagining what you can’t see.

That’s old-school psychological horror thinking, executed with modern precision.

Sound as the True Monster

If there’s one technical element the trailer makes unmistakably clear, it’s this:Sound design is the real antagonist of Undertone.

Composer Shanika Lewis-Waddell and editor Sonny Atkins use audio the way most horror films use creatures. The noises don’t announce themselves. They invade. They linger. They make you question whether you heard anything at all.

This isn’t about loud scares. It’s about low-frequency dread—the kind that sits in your chest and doesn’t move.

In an era where horror often confuses volume with terror, Undertone goes the opposite direction. And that’s exactly why it works.

Why Undertone Feels Perfect for A24

Let’s be blunt: Undertone would not survive in a mainstream studio system unchanged.

This is the kind of film that trusts its audience. It refuses to explain itself. It embraces ambiguity. It understands that fear is subjective—and that the scariest thing is uncertainty.

That makes A24 the ideal home. If you’re a fan of their quieter, more cerebral horror titles, Undertone fits right into that lineage without feeling derivative.

It doesn’t want to shock you.

It wants to unsettle you long after the credits roll.

Release Date, Runtime, and Key Details

• Title: Undertone

• Release Date (U.S.): March 13, 2026

• Runtime: 85 minutes

• Country: Canada

• Language: English

• Director / Writer: Ian Tuason

• Distributor: A24

Premiering at Fantasia in July 2025, the film already carries buzz as a minimalist horror experiment that actually sticks the landing.

Final Verdict: A Horror Film That Knows When to Shut Up

Here’s the honest take: Undertone is not for everyone.

If you need constant action, visible threats, or clear explanations, this will test your patience. But if you love horror that respects your intelligence, trusts atmosphere over spectacle, and understands that fear lives in the margins—this could be one of 2026’s most quietly devastating horror films.

The trailer doesn’t promise answers.

It promises unease.

And sometimes, that’s far scarier.

Undertone arrives in theaters March 13, 2026.

Listen carefully.