The worst moment in the Other Mommy trailer happens over a pot of pasta. Jessica Chastain, home on her lunch break, stands at the stove and asks her eight-year-old daughter whether she can go inside her heart. The kid does not scream. She goes still, the way children go still when an adult they love starts putting words in the wrong order.
Universal released the full trailer online this week after running it exclusively in theaters ahead of The Odyssey, where it built enough word of mouth that people who had not seen it were already asking about it.
Who Made It and When You Can See It
Other Mommy is Rob Savage’s adaptation of Josh Malerman’s 2024 novel Incidents Around the House, from a screenplay by Nathan Elston. James Wan produces through his Atomic Monster banner, alongside Blumhouse Productions and Spin a Black Yarn. Universal has the film in theaters on October 9, 2026, moved back from an earlier May slot.
Chastain plays Ursula, and according to Universal’s own materials she also plays Other Mommy, the presence that arrives wearing her face. Arabella Olivia Clark plays Bela, the daughter. Jay Duplass plays her father, Daddo. The supporting cast includes Dichen Lachman, Arian Moayed, Karen Allen, Sean Kaufman and Adam Silver.
The Book Stayed at Kid Height
Malerman’s novel found its audience partly by refusing the adult vantage point. The story stays with Bela, and the horror is filtered through what a child can name and what she cannot. Other Mommy does not lurk somewhere distant and wait to be investigated. She is in the house, in the closet, at the edge of rooms where a parent has just been standing. That is a hard book to film, because the moment a camera pulls back to an adult’s eye level, the whole engine changes.
One Actor, Two Mommies, No Tell
The dual role is the piece worth watching. Casting one actor as both mother and thing means the film cannot rely on a creature design to tell you which is which, and neither can Bela. Every hug becomes a test. Every soft voice is evidence for the prosecution. If the film commits to that, the danger is not that the monster is in the house. It is that the person you would run to is already standing in the doorway.
Chastain has done maternal horror before, and this is not that. In the trailer she is not protecting a child from something. She is the something, or at least half of her is, and the performance seems built out of warmth held about two seconds too long.
Other Mommy opens in theaters October 9.
