A24 dominated online horror discussions with the release of a new teaser trailer, entitled “It Wants to Be Heard,” for the upcoming horror film The Undertone.

And it didn’t take long for fans — including us — to realize some of the creepy audio in the teaser was music being played backwards. And to reverse that audio.

It may actually be creepier when played forward. Here is the original version, and our reversed audio:

What We Know About The Undertone So Far

The Undertone, from first-time feature director Ian Tuason, debuted at the excellent Fantasia Film Festival last summer. The festival, one of our favorites, was also the one to premiere Skinamarink, which used online fascination to build into a major hit, despite a mere $10,000 budget.

The Undertone hopes to similarly overperform.

The film, which will play the Sundance Film Festival at a midnight screening later this month, follows the host of a popular paranormal podcast who becomes haunted by terrifying recordings that are mysteriously sent to her.

As Sundance explains, “Strained by the responsibility of providing end-of-life care to her dying mother, Evy (Nina Kiri) seeks respite from the loneliness of her fragmented reality. Now living in a house full of sentimental keepsakes and memories, her sanity and structure lies within her work on a supernatural podcast, The Undertone. While she usually plays skeptic to the creepy (and often disturbing) audio files sent to her by co-host Justin (Adam DiMarco) for podcast fodder, the latest submission hits differently.

“A series of 10 unheard recordings from a young pregnant couple are unfurled one by one, each more ominous than the last,” the Sundance summary continues. “As Evy draws parallels to her current plight, hidden messages manifest, pushing her further toward madness.”

Deadline reported in August that A24 acquired the film in a bidding war, “and that the deal was for mid-7 figures.”

In her Fantasia Fest description of the film, programming director Carolyn Mauricette wrote, “Fans of SKINAMARINK and I AM THE PRETTY THING WHO LIVES IN THE HOUSE will love this slow-burn nightmare that will make hackles on your neck rise and your blood chill.”

The film’s eerie marketing campaign has also drawn comparisons to those of Weapons and Longlegs, the latter of which came from I Am the Pretty Thing That Lives in the House director Osgood Perkins.

Main image: Nina Kiri appears in undertone by Ian Tuason, an official selection of the 2026 Sundance Film Festival. Courtesy of Sundance Institute. Photo by Dustin Rabin.