Other Mommy hits theatres Friday, October 9, 2026 — and it’s already drawing attention not just for its chilling premise, but for the quiet moment that sparked it all. The film, directed by Rob Savage and produced by James Wan under Blumhouse-Atomic Monster, is an adaptation of Josh Malerman’s novel Incidents Around the House, published in June 2024. The story’s roots trace back more than a decade before the book was written. According to Malerman himself, the idea began with a real-life anecdote: his brother once told him about putting their child to bed and hearing the child say goodnight, twice. The second time, the child said it to ‘Other Mommy’. That single line stuck. Malerman recalled the moment during an interview with The Nerd Daily, saying, “I’ve had the idea for some 13 years.” He went on to write the outline on an office wall before finalising the novel. The book’s opening chapter mirrors that incident almost exactly: eight-year-old Bela says goodnight to her mother, then repeats it. This time to ‘Other Mommy’. Her father laughs it off. Her mother pauses, glances through the door crack, and leaves. In the narrative, ‘Other Mommy’ is not a ghost or a spirit, it’s a presence that emerges from Bela’s closet, shaped like her mother, asking daily: Can I go inside your heart? As the family’s tensions grow, so does the threat. The entity doesn’t just mimic. It demands. The novel earned Malerman a Bram Stoker Award nomination and a Locus Award finalist nod, with Stephen King calling it “the rare novel that’s authentically scary.” The film version, written by Nathan Elston, brings that unease to screen. Jessica Chastain stars as both Ursula, the real mother, and the entity that wears her face. She described the creature’s smile as deliberately unnatural, not warm, but tense, built to feel like skin being pulled tight. It’s meant to look safe to a child while hiding something far more invasive. The supporting cast includes Arabella Olivia Clark as Bela, Jay Duplass as Daddo, Karen Allen as Grandma Ruth, and Dichen Lachman and Arian Moayed in key roles. Universal Pictures handles distribution, describing the film as “a terrifying trip into the darkening world of a young girl” who forms a bond with a sinister force in her home. The entity in the movie is visually distinct from the book. Where it has eyes that move around Bela’s head, but here, it’s a perfect double. The film arrives at a time when audiences are seeking stories that linger beyond the credits, and this one may do just that. Not because of jump-scares, but because of what it asks: how much can a child’s imagination hold before it becomes real?