Jessica Chastain knows her way around a horror movie. Now she’s back with one that puts a seriously unsettling spin on the idea of a family nightmare.
Other Mommy arrives in theaters Friday, October 9, with Chastain playing a mother—and something that looks exactly like her.
If that sounds creepy already, that’s the point.
So, What’s Other Mommy About?
The movie follows Bela, an eight-year-old girl whose family life is already becoming complicated.
Then she encounters a mysterious presence in her home.
She calls it Other Mommy.
The unsettling part? Other Mommy looks remarkably like Bela’s real mother, Ursula.
From there, the movie turns a familiar horror setup into something much more personal. Instead of simply wondering what’s lurking in the dark, Bela has to figure out who she can actually trust.
Jessica Chastain Is Playing Two Roles
Chastain takes on both sides of the movie’s central mystery, playing Ursula and the entity that takes on her appearance.
It’s another supernatural outing for the actor, who previously starred in Mama and It: Chapter Two. This time, though, the familiar face of a mother becomes part of the threat.
Arabella Olivia Clark stars as Bela, with Jay Duplass playing her father, Russ.
The cast also includes Karen Allen, Dichen Lachman, Arian Moayed, Sean Kaufman and Adam Silver.
Behind the Scenes
Other Mommy is directed by Rob Savage, whose horror credits include Host and The Boogeyman.
Nathan Elston wrote the screenplay, with the movie produced by Blumhouse, Atomic Monster and Spin a Black Yarn and released by Universal Pictures.
James Wan is among the producers, while original author Josh Malerman serves as an executive producer.
Yes, There’s a Book
The movie is based on Malerman’s 2024 horror novel Incidents Around the House.
The book’s central premise—an unsettling presence entering the life of a young girl—makes the jump to the screen with Other Mommy taking its name from the story’s mysterious entity.
You don’t need to have read the novel before seeing the movie, but book fans will undoubtedly be curious to see what made the transition from page to screen.
What Kind of Horror Is This?
Think supernatural horror with a psychological edge.
There’s a haunted-home element, family tension and plenty of uncertainty surrounding the mysterious entity. But the movie’s biggest hook may be its simplest:
What if the monster looked exactly like someone you loved?
Other Mommy opens in U.S. theaters October 9, 2026.
The Bottom Line
Other Mommy takes one of the most basic fears from childhood—something strange hiding in the house—and gives it a disturbing makeover.
A mysterious presence. A troubled family. And a face that looks a little too familiar.
Sometimes, the scariest thing isn’t what you don’t recognize. It’s what you do.
