**"Other Mommy,"** the supernatural horror film directed by Rob Savage and produced by James Wan under the Blumhouse Atomic Monster banner, opens wide on October 9, 2026, positioning its Tomatometer score as a key test of high-profile horror appeal. Jessica Chastain stars in a dual role as a mother and the sinister entity mimicking her, supported by a cast including Jay Duplass and Arabella Olivia Clark, with the story adapted from Josh Malerman’s 2024 novel *Incidents Around the House*. Recent marketing momentum includes a second trailer in mid-September and promotional featurettes highlighting Chastain’s performance and the film’s psychological tension. Pre-release sentiment draws from Savage’s prior genre work like *Host* and *The Boogeyman*, plus Universal’s strong 2026 box-office track record, though horror scores remain sensitive to early critic consensus on originality, scares, and pacing once reviews post around opening weekend. The market will likely hinge on embargo timing and initial aggregator scores in the days following release.