undertone plot recap, spoiler-light
In the horror mystery film undertone, host Evangeline Babic and her friend Justin operate a popular supernatural podcast. While Evy approaches these spooky reports with skepticism, Justin treats them as absolute truth. Their dynamic shifts dramatically when an anonymous tipster delivers ten mysterious audio files.
The recordings capture a couple, Mike and Jessa, dealing with unsettling sleep-talking phenomena. As Evy and Justin broadcast these eerie clips, they begin investigating hidden backward messages in innocent childhood nursery rhymes. Outside of the podcast, Evy faces intense personal turmoil.
She discovers she is pregnant, experiences severe anxiety regarding her maternal fitness, and continues tirelessly caring for her unresponsive mother at home. Strange occurrences start plaguing Evy's living space, including flickering lights and displaced religious statues. Unbeknownst to the hosts, listening to the complete set of audio files and discussing the ancient demon Abyzou invites a terrifying and inescapable supernatural presence directly into their lives.
