A podcast host is haunted by cryptic audio recordings in the second trailer for undertone.

Billed as “the scariest movie you’ll ever hear,” the slow-burn horror film will be released in theaters on March 13 via A24.

Nina Kiri (“The Handmaid’s Tale”) stars as Evy, a paranormal podcast host who moves into her dying mother’s house to be her primary caregiver.

When she receives audio recordings of a young pregnant couple experiencing supernatural noises, she realizes the woman’s story mirrors her own. Each new recording scratches at her sanity, drawing her into a fate she cannot escape.

Adam DiMarco (“The White Lotus “), Michèle Duquet (The Virgin Suicides), Keana Lyn Bastidas (“The Hardy Boys”), Jeff Yung (The Shrouds), and Ari Millen (“Orphan Black”) round out the cast.

Writer-director Ian Tuason makes his feature debut on the project, shot on location inside his childhood home in Toronto. He’ll next helm the new Paranormal Activity movie.

“With the added element of audio in undertone, it’s not just imagining what you might see, it’s also imagining what you might hear,” Tuason explains. “It’s the intermingling of the visual and auditory that amplifies the horror.”

Slaterverse Pictures’ Dan Slater and Black Fawn Films’ Cody Calahan produce. Executive producers include Steven Schneider & Roy Lee for Spooky Pictures, Chad Archibald for Black Fawn, Brit MacRae & Daril Fannin for Kino Studios, and DimensionGate.

Joe Lipsett wrote in his 4.5-skull review, “I can’t remember the last time a movie made every hair on my body stand up, but undertone got me good.”

The film premiered at last year’s Fantasia Film Festival, igniting a seven-figure bidding war, and made its US debut at Sundance last month.

undertone is rated R for “language.”