‘Other Mommy’ Turns Josh Malerman’s Novel ‘Incidents Around the House’ Into a Supernatural Horror Film

‘Other Mommy’ stars Jessica Chastain, is directed by Rob Savage and written by Nathan Elston, and is based on Josh Malerman’s book ‘Incidents Around the House’. Universal is releasing the film widely in the United States on October 9. For anyone wondering what ‘Other Mommy’ is based on, the answer is a recent horror novel rather than an original idea.

The source novel was published in 2024. An adaptation was announced in April 2025, and Chastain also plays the supernatural entity of the title. That timeline shows how quickly the book moved from shelves to a major studio release.

What ‘Other Mommy’ Is Based On

The film is based on the New York Times bestselling novel ‘Incidents Around the House’ by Josh Malerman, the author of ‘Bird Box’. The book was published by Del Rey. Promotional material now frames the novel as the inspiration for the movie.

Some viewers noticed a resemblance to ‘Coraline’ after the first trailer appeared. One explainer points out that the film is not inspired by that story, and says its source is another book. The same piece notes that the name and the entity’s spider-like nature invite the comparison.

The project was first known by the title of the novel, and it was widely suspected the filmmakers would not keep it. It was retitled ‘Other Mommy’ in July 2025, which aligns it more closely with the book’s central antagonist. The shorter name also makes the horror easier to grasp at a glance.

The Novel ‘Incidents Around the House’ and Its Premise

The novel is told through eight year old Bela, who loves her family and also faces a malevolent entity that asks her every day whether it can go inside her heart. When strange incidents suggest the entity is losing patience, Bela understands her family will pay unless she says yes. The question is the engine of the story.

Other reviewers describe the book as a story of Bela, her parents Ursula and Russ, known as Mommy and Daddo, and a closet dwelling entity. The official description adds that cracks in her parents’ marriage appear alongside the supernatural incidents. That domestic strain is a key part of the setup.

One library review notes that the book shows that a story does not need a crumbly mansion to unsettle readers. The same review says the narration captures how children accept things adults have learned to reject. That child’s eye view is likely the hardest element for any adaptation to preserve.

Josh Malerman’s Path From Page to Screen

Malerman is a New York Times bestselling author whose debut novel ‘Bird Box’ inspired the Netflix film of the same name. ‘Incidents Around the House’ was published following the success of that earlier book. His name carries weight with horror audiences who remember the earlier adaptation.

The novel drew strong praise, with Esquire naming it among its best horror books of 2024. Author Grady Hendrix described it as the monster that lives inside your closet. Notices like these helped position the book as a ready made film property.

Malerman is among the executive producers of ‘Other Mommy’. That credit suggests the author remains involved as the film reaches theaters. Josh Malerman’s name also sits alongside producer James Wan on the project.

How Rob Savage’s Adaptation Shapes the Story

Savage, whose credits include ‘Host’ and ‘The Boogeyman’, directs from a script by Nathan Elston of ‘Succession’. Atomic Monster and Blumhouse are producing in association with Spin a Black Yarn for Universal. The team brings a clear horror pedigree.

The film follows Bela, whose home life is already strained when a sinister presence she calls Other Mommy begins emerging from her closet each night. The entity bears a striking resemblance to her actual mother. Chastain plays both Ursula and Other Mommy, and the cast includes Jay Duplass, Arabella Olivia Clark, Dichen Lachman and Karen Allen.

Universal moved the release from May 8 to October 9, placing it against other major releases that month. The first trailer debuted ahead of select screenings of Christopher Nolan’s ‘The Odyssey’. Whether Chastain’s dual performance sells the book’s central fear of a mother who is not quite a mother will be the real test, so which version of Other Mommy do you think will unsettle audiences more, the one on the page or the one Chastain brings to the screen?