In a quiet home, Evangeline “Evy” Babig tends to her ailing mother, Evelyn, singing soft lullabies as night deepens. The scene sets a gentle, intimate mood that quickly tilts toward unease when Evy and her friend Justin Manuel decide to record their weekly horror podcast, The Undertone. Evy remains the skeptic, while Justin leans into belief, and the pair trade notes about their vulnerable living situation—Evy’s mother’s fragile health and a partner who isn’t always present, Darren. What begins as a routine recording soon spirals into a disturbing mystery fueled by a string of ominous audio files.
Their first topic centers on a viral video titled “I Feel Wonderful,” an image of a smiling woman that appears to distort—and, as stories claim, drives dozens to tragedy. Justin then shares ten audio recordings from an anonymous sender, all centered on a couple named Jessa and Mike. The first clip captures Mike recording Jessa as she sleep-sings “London Bridge.” In the second, Jessa sleepwalks and repeats the same song in reverse; when played backward, it seems to murmur the words “Mike kill all.” This prompts Justin to dig into history and folklore, including a reference to Eleanor of Provence and the ominous lore surrounding London Bridge. The duo also probes the darker meaning behind the nursery rhyme “Baa Baa Black Sheep,” foreshadowing a thread that will braid myth, music, and menace.
As the night unfolds, the third file shows Jessa waking Mike after a disturbance in the house—the running water—an event that makes Evy feel as though the noises are creeping through her own walls. The atmosphere thickens with the sense that something ominous has seeped into Evy’s home. The podcast winds down with a decision to resume in a few days, leaving the audience with more questions than answers.
The following morning brings a more personal storm: Evy learns she is pregnant, but the news sits heavy with uncertainty as she grapples with whether to keep the baby. Evelyn’s condition worsens, and a nurse warns that Evelyn’s breath carries a “death rattle,” a chilling hint that time may be running out. Throughout the week, Evy shoulders the demanding tasks of caregiving—bathing, cleaning, lifting, and comforting her mother—while a creepy crayon drawing of a dark, faceless woman surfaces in Evy’s drawers, hinting at a lurking danger.
That night, Evy revisits the audio files and plays the fifth clip in reverse, only to hear a chilling phrase that seems to morph into something far more sinister: a backward whisper that, when reversed again, hints at a figure who speaks through the recordings. Evy’s vigilance grows as eerie phenomena intensify—flickering lights, unexpected noises, and the return of a Virgin Mary statue that materializes in defiance of Evy’s attempts to banish it. The podcast moves on to new discoveries: the fourth audio file features Jessa interacting with a creepy doll that whispers unsettling lines like “I like it here in the dark,” while Mike and Jessa awaken to what sounds like a heavy thump, which Evy suspects is faulty plumbing but may be something more insidious. The fifth file’s backwards phrases terrify Mike, pushing the duo to continue the investigation even as fear takes hold.
Driven by a growing sense that something supernatural is tied to the tapes, Evy and Justin reverse the mysterious recordings to uncover a single, chilling name: Abyzou. They learn that Abyzou is a mythical demon—the patron saint of cursed mothers—who preys on women with children, causing miscarriages or pushing mothers to harm their infants. This revelation casts a new light on the grim pattern unfolding around Evy and Jessa and raises a horrifying possibility: the tapes may be more than hoax or fiction; they could be a conduit for a dark presence.
As Justin plays the sixth and seventh files, the couple’s voices overlap in unsettling ways, and a baby’s cry intrudes on Jessa’s snoring. Jessa’s scream—frantic and fear-driven—seems to hint at something lurking by the kitchen sink, though Mike dismisses it as a neighbor’s baby. The sender’s identity remains a mystery, and emails keep bouncing back as the duo contemplates whether to abandon the investigation. Despite the creeping dread, Evy urges them to press on, curious to see where the truth will lead.
The eighth file escalates the tension: Jessa awakens Mike again to banging in the walls, and the familiar lullaby of “Baa Baa Black Sheep” resurfaces, mingling with increasingly disturbing baby noises and escalating screams. The ninth file contains a chilling combination of fear and revelation, as Jessa’s voice hints at being watched and warns that Abyzou may be coming for them. Viewers begin to call in with stories of neighboring families affected by the tapes, including a pregnant woman who once rented a basement and later faced a tragedy involving her own child. The two hosts wrestle with the possibility that the recordings are not a hoax but a doorway to real danger.
A series of calls deepens the sense of peril: a caller asks to speak with “Mary,” Evy’s considered name for her unborn child; another caller warns that listening to the ten tapes awakens Abyzou; a final caller, “Abby,” pleads for help with a crying baby, and the line fades into the night with the sense that something has already claimed control behind the walls. The duo’s investigation becomes a haunted chorus of voices and visions: Abyzou’s symbols appear on walls, the “I Feel Wonderful” video morphs into a terrifying image, and Evy glimpses Evelyn moving on the edge of consciousness in the bathroom.
With the tension spiraling, Evy ascends the stairs only to find her mother awakening and the bathroom light turning on by itself. Evelyn rises slowly as Evy tries to speak to her, and the sense of danger thickens into a final, devastating moment. As the podcast closes, Evy and Justin are overwhelmed by distorted sounds and a blurring line between reality and the recording. Evy sees the first concrete signs of Abyzou in the house, and the imagery tightens around the two women as the film hurtles toward its climax. The camera cuts to black while Evy’s scream echoes, and her voice distorts, repeating a backward phrase, “Come in, Abyzou,” as the haunting final image lingers.
> Come in, Abyzou
In the end, the story threads together a cautionary tale about belief, the vulnerabilities of caretaking, and the way old myths can seep into the present, turning a night of shared horror into a confrontation with forces that may be beyond anyone’s control. The film leaves Evy—and the audience—facing a haunting question: what happens when the lines between a carefully crafted podcast, a dark legend, and a mother’s fear become indistinguishably intertwined?
