Review: In 'Other Mommy', Jessica Chastain becomes the monster that mimics her own character — but the film runs from its creature so fast it forgets to be scary

'Other Mommy' hit theaters on Friday (Oct. 9) with an irresistible premise: 7-year-old Bela (Arabella Olivia Clark) is haunted by a shape-shifting 'imaginary friend' that mostly appears with the face of her mother, Ursula. Jessica Chastain plays both — the mother and the entity. Directed by Rob Savage ('Host') from Josh Malerman's ('Bird Box') novel 'Incidents Around the House', with a script by Nathan Elston and James Wan producing, the 93-minute film also features Jay Duplass as the father, Russ, Karen Allen as Grandma Ruth, Arian Moayed, and Dichen Lachman as an exorcist.

When it works, it works well. Savage stages the creature attacks with polish, and they deliver the most memorable jolts; the sound design, built mostly from silence and ambient noise, is also used smartly, as Simon Abrams noted at RogerEbert.com. The problem is everything in between. The family spends the film fleeing the monster instead of trying to understand their daughter, Ursula and Russ's strained marriage is barely sketched, and threads like the séance and the family's religious background go unexplained. Chastain and Duplass are asked to imply huge emotions the script never builds — at heart, it is the same high-concept chase movie as Savage's 'Host', just with a bigger budget.

U.S. critics were harsher than most: Variety called it one of the year's most limp films, Bloody Disgusting (2 out of 5) found it 'devoid of tension', and SCREEN-SPACE pointed to gimmicky direction and a half-baked message; the most generous, like Heaven of Horror (3 out of 5), acknowledge some genuinely sinister moments. Audiences, however, showed up, and the film leads the weekend box office. For a quick October scare, it delivers; for anyone hoping Chastain and Malerman's book would yield a horror film about motherhood with something to say, it disappoints. Score: 4.5/10