ɫɫ��

“Weapons” is his sophomore effort and it’s more ambitious than his first, It’s told in chapters from the perspective of various interweaving characters — like a horror version of “Magnolia” — and explores the ripple effects from a tragic event. But it often lags and slackens on its way to a gruesome end, with a reliance on sorcery that seems like a cop-out.

“This is a true story,” says a child narrator at the start of the movie, only for that technique to disappear shortly afterward. “A lot of people die in a lot of weird ways.” Indeed: There’s some fork stabbings, an assault with a vegetable peeler and one victim takes so many headbutts that his skull caves in.

The event at the movie’s heart is the disappearance of 17 third-graders from a single class in the middle of the night in the leafy town of Maybrook, Illinois. Ring cameras catch them opening their front doors and rushing out, not to be seen again. Only one child from the class showed up the next day at school.

Everyone is baffled and frustrated. Did the kids plan it together? Were they sent a coded message via a video game or social media? Why was one child from the class seemingly spared? And does the teacher know more than what she’s letting on?

who plays the teacher, offers us a fascinating, spiky character, prone to pity parties and self-righteous outbursts. She’s also seductive and manipulative and growing reliant on booze to cope with the suspicions leveled at her. At one point, someone scrawls the word “witch” on her Toyota. The town will soon know what that word really means.

Garner — who is doing double duty this summer as the Silver Surfer in wow, quite a range — is warned to stay away from the case but refuses, doing her own stakeouts and trying to speak to the only surviving classmate. “We are the only ones left,” she says.

Cregger being Cregger, there are lots of misdirections, paranoia and an almost existential sense of humor, usually mocking horror movie conventions (and, in this case, the movie “Willow”). In “Weapons,” he also nicely shows the quiet resilience of kids and their ability to face daily horrors and keep going, trying to help those they love despite creepy awfulness.

The upset parents are represented by Josh Brolin’s broken father, whose son was one of the 17 who fled. He sleeps in his son’s room, wracked by guilt that he couldn’t protect someone so dear. He soon will join forces with the teacher to uncover the secret of what made the children run.

They will also collide into a local drug user/low-level criminal, played superbly by Austin Abrams, whose bumbling, comic relief is welcome. Amy Madigan is unrecognizable and utterly mesmerizing as an oddball aunt of the surviving boy, a splendid Cary Christopher.

“Weapons” is best before the final third, when we learn of an outside force that may have triggered all this misery. Cregger seemed to be on more solid footing mocking suburban life, showing the savagery below the mowed grass pleasantries, the quiet desperation inside marriages and the corruption of small-town police departments.

If “Barbarian” came out of left field three years ago and heralded an exciting new voice in filmmaking, “Weapons” doesn’t disappoint but it doesn’t have the advantage of surprise. It will, at the very least, make you feel a little dread when the clock hits 2:17 a.m.

“Weapons,” a Warner Bros. Pictures release hitting theaters Friday, is rated R for “strong bloody violence and grisly images, language throughout, some sexual content and drug use.” Running time: 128 minutes. Two and a half stars out of four.