God, what I wouldn’t give to see Joan Crawford and Bette Davis in “Mothers’ Instinct,” the pallid suspense thriller that skipped through theaters like a stone on its way into the ocean of on-demand. Back in the heyday of the great studios, they knew to treat melodrama like grand opera: sweeping gestures, crazy-eyed divas front and center, emotions amped up to reach sobbing audiences in the back row.

Instead, Benoit Delhomme’s overly decorous period piece casts Anne Hathaway and Jessica Chastain in the lead roles of suburban neighbors who wage psychological warfare after a tragedy destroys their friendship. Both women are fine actors, with the statuary on their shelves to prove it. But roles like this don’t call for fine acting. They call for BIG acting, the kind that leaves a moviegoer slack-jawed at the passions erupting off the screen. The sort of performances that obliterate the line between high art and trash.

And “Mothers’ Instinct” is, at heart, pretty good trash, an adaptation of a well-regarded beach read by Belgian thriller writer Barbara Abel that has been filmed once before in France (“Duelles,” 2018). The new film is set in an Eisenhower-era neverland, where the lawns are perfectly manicured and the housewives perfectly gowned. Celine (Hathaway) and Alice (Chastain) live next door to each other in stately, well-appointed homes with their respective husbands Damian (Josh Charles) and Simon (Anders Danielsen Lie) and respective 8-year-old sons Max (Baylen D. Bielitz) and Theo (Eamon O’Connell), the last two best friends.

The unthinkable happens early on: Max dies after an accident that Alice witnesses but is unable to prevent, and the previously gracious Celine disappears into a black hole of grief that unmoors the bond between the two women. Guilt, recriminations, suspicions — all are tamped awkwardly beneath a veneer of strained politeness, but beneath the surface, madness is bubbling.

But which one’s the crazy one? Chastain’s Alice is established as the more insecure of the two, a former journalist still unsure whether choosing marriage and motherhood over career was the right choice. (Her husband blandly informs her she can do some reporting for Theo’s school newspaper.) She’s hesitant and cool around her son, too, who responds more naturally to the wounded bird that is his dead friend’s mom. Is Celine (who we’re told can’t have another child) spending too much time with Theo? Does she have a darker game in mind? Or is Alice paranoid enough for a return trip to the sanitarium her husband sent her to after a bout of postpartum depression?

On a technical level, “Mothers’ Instinct” is swank as hell, with impeccable costumes, richly hued camerawork, and a score by Anne Nikitin that swoons and throbs and does all the emotional lifting. Which is good, because the acting doesn’t. I’m not saying that Hathaway and Chastain give bad performances; they don’t. They givetastefulperformances — exactly what is not called for, except for maybe at the beginning. By the end, this should be King Kong vs. Godzilla — two larger-than-life actresses going at each other with their Oscars.

(How are Charles and Lie as the husbands, by the way? Doesn’t matter — in melodrama, the men are always interchangeable.)

It’s a critic’s failure to gauge the movie he wishes had been against the movie that is, but in this case the movie that is is disappointingly bloodless, cold rather than chilling, with a payoff that isn’t shocking so much as an admission that we’ve spent 90 minutes we’ll never get back. Hathaway’s portrayal, a dark and thoughtful piece of acting, is the best thing here — and also the most beside the point. She plays Celine as an elegantly tortured mother dear, when what’s called for is Mommie Dearest.

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Two stars. Unrated.Available on Apple, Google Play, Prime Video and YouTube.Containsmild violence, psycho mommies. 94 minutes.

Rating guide: Four stars masterpiece, three stars very good, two stars okay, one star poor, no stars waste of time.