The Czech and Slovak joint production “Nightsiren” is a witchy tale about superstition, ritual and the function of witchcraft in an age-old patriarchy.

Director and co-writer Tereza Nvotová has conjured up an obscure, opaque thriller of symbolism and violence, old grudges and dots that don’t quite connect. When the events of this film cross that fateful date, “midsummer,” we have our easiest, most apt analogy for it.

It’s a slightly dumber “Midsommar.”

Years ago, a girl fled her brutal, widowed mother and in so doing caused the death of her little sister. Twenty years later, Sarlota (Natalia Germani) returns with her backpack, some supplies, a big wound she’s treating, psychic scars she’s ignoring and a guilty conscience she’s not quite reconciled.

Local yahoos on ATVs accost her as she rummages through a building on her mother’s old property.

“The witch dropped a tree on the last person who stayed here,” they warn (in Slovak with English subtitles).

But the armed tough guys are a little rattled with she tells them her name. Her mother was the one they called “the witch.” The place is cursed.

For real answers about this unfriendly village and what’s going on here Sarlota turns to one seemingly sympathetic older woman, and to the free spirit Mira (Eva Mores).

But even Mira can’t tell her what happened to this “wild child” her mother kept around after Sarlota fled. Might that be the sister she’s long believed died? And as we’ve seen the same body at the bottom of a cliff that Sarlota has, we wonder “Was it witchcraft that brought that wild child back?”

Actress turned director Nvotová’s film has a dreamlike quality to its folklore and a grim women-in-a-man’s-world reality to the daily indignities and violence the women in this village endure.

Some seasonal ritual has the menfolk dunking every woman they can get their hands on in water. Sarlota isn’t having it.

Every time it seems she might be fitting back in where she grew up, something about livestock or the local children comes up to shine suspicion on her anew.

Nvotová — “Filthy” was her debut feature — goes for tone more than linear coherence in this somewhat slow sex and superstition and gender-politics tale. Situations aren’t explained, various aspects of Sarlota’s physical state hinted at with contradictory explanations.

And just when you let the “witch” thing slip to the back of your mind as the film plods forward, here’s a moment where one suspected witch must strip and another where Sarlota finds herself stumbling into a witches’ orgy in the woods, nude bodies cavorting about a bonfire.

“Nightsiren” is too ponderous and self-serious to ever earn the label “exploitation,” but with all the nudity, sex and sexual violence in a somewhat less than it seems story, that’s where it belongs.

That laborious “chapter” heading editing and organizing principle (faddish screenwriters everywhere do this) is trotted out. And while the picture reaches a climax and wanders into an ending, there’s not much pace or ugency to any of it.

Even connecting with our heroine seems a stretch, despite her and Mira standing up to the child beating-spouse-abusing locals. Germani’s performance has purpose, but no pathos.

It holds one’s interest, if only to make the viewer wonder if this connection to that new state of affairs will ever be expained, or if more semi-gratuitous nudity will pop up between the bonfires, campfires and housefires that are what stick in the mind’s eye about “Nightsiren.”

Rating: unrated, lots of violence, nudity

Cast: Natalia Germani, Eva Mores, Juliana Olhová, Marek Geisberg, Jana Olhová and Noel Czuczor

Credits: Directed by Tereza Nvotová, scripted by Barbora Namerova and Tereza Nvotová. A Breaking Glass release.

Running time: 1:47