Sultry, sweaty and sufficiently bizarre, “Love Lies Bleeding” is a neo-noir thriller packed with barbells and bullets that’s fearless in its depiction of lesbian love and over-the-top mayhem.

Director Rose Glass follows up the unholy terror of 2019’s “Saint Maud” by rubbing a grimy sheen across a zesty retro combo of a revenge flick, addiction narrative, body horror show and queer love story. Newcomer Katy O’Brian is sensational as a bisexual bodybuilder who gets mixed up in some bad business – with Kristen Stewart as her troubled romantic interest – in a muscular yet incomplete yarn (★★★ out of four; rated R; in select theaters now, nationwide Friday) exploring the seedier corners of Americana.

In small-town New Mexico circa 1989, Lou (Stewart) oversees a ramshackle gym where her days are spent unclogging nasty toilets and laminating membership cards. One night, Jackie (O’Brian) stops by on the way to a competition in Las Vegas: Working her ripped physique garners male attention, though she only has eyes for Lou, and vice versa.

They hit it off, and Lou taps into her steroid supply to help Jackie get extra jacked for the big day. But the more Jackie immerses herself into Lou’s tumultuous world, the more trouble she finds. Jackie starts working for her new love’s skeezy estranged dad (Ed Harris), the bug-chomping criminal owner of a local gun club and also meets the abusive husband (Dave Franco) of Lou’s sister (Jena Malone).

An act of familial violence goes too far, the vengeful aftermath tests Jackie and Lou’s fledgling relationship, Lou threatens to expose her father’s shady dealings, and the bodies pile up as our lovers get desperate.

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Lives go off the rails, but Glass keeps the plot from following suit, weaving in a dark sense of humor (there’s a whole bit with a jawless corpse) and a fantastical bent. “Bleeding” gets weird but not too weird, and the intense chemistry between Stewart and O’Brian powers an insightful exploration of how love can save just as easily as it can turn one’s entire existence into pure chaos.

Stewart is solid as the frazzled Lou, who struggles to find steadiness even when Ms. Right walks through her gym door. But none of it works without O'Brian, whose first lead big-screen role is a performance she nails physically and emotionally. A former bodybuilder herself, the actress superbly navigates the arc of a hulking character transformed by steroids and her increasingly volatile situation. O’Brian finds the unsettled soul underneath Jackie’s rippling muscles and lets her loose, flaws and all, but is also game for a healthy amount of strangeness too.

When Jackie and Lou aren’t together, the movie suffers because neither of their individual points of view are particularly strong. Bits of their backstories come out but not enough for two people whose cryptic pasts seemingly inform their unhinged present. You’re left wanting more – they’re both called “monsters” by different people, which does pay off in a sense – in a film that otherwise is pretty good at juggling style and substance. 

“Love Lies Bleeding” is a blood-soaked throwback to '80s erotic thrillers and action cinema but also Glass’ deconstruction of cinematic hypermasculinity through a female lens. Instead of dudes named Schwarzenegger and Stallone, it’s a woman named Jackie with the veiny biceps, who when offered a gun, says she doesn’t need one: “I prefer to know my own strength.” For this movie, that is the teaming of Stewart and O'Brian, who's about to be movie lovers' powerful new obsession.