A24’s Undertone Review: A Cerebral Masterclass in Sonic Terror

Chase Gifford
7 hours ago
5 min read

“If you don’t want to be scared in a horror film, don’t close your eyes. Close your ears.” – Eli Roth

A good horror director knows that most of their audience will already be established horror movie fans. And for longtime fans of the genre, they grow savvy to the ways of horror tropes and cliches. I think one of the most important aspects of a successful horror movie is subversion. Subversion of expectations and assumptions to deliver a surprising and effective payoff. The figure lurking in the dark. The presence of someone standing in the background of a bathroom mirror. The empty jumpscare that reveals something or someone who poses no threat, meant to elicit a small giggle or sigh of relief. These are common, predictable, and even cheap. Cutting all sound before a loud and sudden noise is not scary, it’s reactionary. It’s a cheap sonic sugar-high—loud, fleeting, and ultimately as disposable as a paper plate. A seasoned filmmaker could do it but so could my nextdoor neighbor and she works at Lowe’s.

I think it’s a perversion of audio which if used correctly can be a horror movie’s greatest asset. Sound can suggest. Sound can demand. Sound can be gentle or it can be aggressive. Finding the aural sweet spot can make the difference between a great cinematic experience and a terrible one. Masters of sound in the horror genre include James Wan, Mike Flanagan, Robert Eggers, and Guillermo del Toro to name a few.

James Wan created a modern haunted house masterpiece with The Conjuring utilizing old school techniques and obeying the rule of zero empty jumpscares with creaking doors, whispers from the shadows, echoes of voices long since passed, and something as profoundly simple as wind cutting through tree branches.

Mike Flanagan is finally and rightfully gaining his notoriety but before he would become a household name in horror, he created a brilliant home invasion thriller ominously titled, Hush. This is an entire premise surrounding the concept of sound or rather lack thereof by creating a deaf heroine, isolated and incredibly vulnerable. Her handicap forces her creativity to combat an armed psychopath determined to torture her mentally and physically before ultimately killing her. Often cutting the sound for the audience, it places you in her shoes making you question how you might handle such a situation where help is not an option and you never hear the threat coming.

Undertone by its very name suggests a variation of sound will not only play a role in the impending events but will be pivotal in how things unfold and where the answers to its mystery will be found. Whether they should be found or not is another question entirely. To watch this, at least for the first time, on something like a computer or phone would be such an injustice against what it’s trying to achieve. Something like the Dolby Theatre where I saw it took me for a ride I wasn’t always sure I was prepared for and that is the thrill of it. Like being stuck on a roller coaster with second thoughts but the train has already left the station. It’s best just to hang on and grit your teeth.

The film centers on a skeptical podcaster who receives a series of disturbing, unverified audio files. As she and her co-host—a firm believer in the paranormal—analyze the recordings, they are drawn into a narrative of a supposed demonic possession. While her co-host is quick to accept the supernatural, she remains anchored in logic, desperately searching for a rational explanation for the guttural, inhuman sounds bleeding through her headphones and into the very architecture of her home. What began as a quest for viral content quickly curdles into a claustrophobic reality; the audio is no longer just a source of 'listens' for an audience, but a sonic infestation that has transformed her private sanctuary into a space of genuine, unfiltered peril.

For the begrudging horror fan, Undertone could be perceived as an obvious budgetary limitation, with a premise that leans on sound design rather than the explicit visual inferences typically used to illustrate a demonic upheaval. I choose to see it as a masterclass in not only sound design, but as an illustration of imagination as a tool more powerful than any form of visual appeasement. The director never gives into the audience’s hopes for a glimpse of the threat and simply leaves it to us to decide based on descriptions of what this myth entails and what previous incidents claim happened. No full CGI demon reveals with this one. I think to show anything in its entirety would be to betray the very title of the movie. To adhere to a premise of an auditory menace looming and threatening emphasizes what the intentions of this story are and that is to aurally thrash and plague the audience with audio steeped in inordinate imaginative possibilities.

The cinematography further reinforces this auditory siege by weaponizing negative space. The camera frequently isolates her in the frame, pushing her off-center to the right to emphasize the yawning emptiness of the kitchen behind her. We are forced to peer through a glass door, waiting for a shadow to streak across the glass—a visual baiting that mirrors her own growing dread. Even more claustrophobic is the recurring low-angle shot from her podcast table; looking up over her left shoulder, the lens captures a looming, pitch-black hallway.

Thanks to earlier establishing shots of the home’s architecture, we know that darkness leads to the staircase of her dying mother—a woman whose 'deathbed unrest' serves as a tether to the very supernatural forces the protagonist is trying to debunk. It is a masterful use of spatial tension, forcing the audience to guard her back while she remains dangerously absorbed in the very sounds that are inviting the threat in.

It is crucial to understand that Undertone carries the A24 pedigree, leaning into a cerebral, arthouse sensibility that stands in stark contrast to the more mainstream Blumhouse model. Where a Blumhouse production might hold the audience’s hand—walking them through heavy exposition and telegraphed jump-scares—this film refuses to placate any preconceived notions of what a 'typical' horror movie should be.

It is an auditory nightmare with no interest in spelling out its terrors. By rejecting the hand-holding of traditional studio horror, the director treats the viewer not as a participant in a sonic haunting that demands—and rewards—a more disciplined kind of attention. If you are looking for a movie that explains itself, look elsewhere; but if you are ready to be aurally thrashed by a story that trusts your imagination more than your eyes, Undertone is a haunting you won’t soon forget.