Syrupy red blood oozing between champing white teeth: If there’s a signature image in Jennifer Reeder’s “Perpetrator,” that might just be it. It’s a striking horror motif but, jumbled in amongst so many other striking horror motifs — nose splints and tattered school uniforms, bloodied fishnet stockings and features-blurring plastic facemasks — by the third or fourth repetition, it loses its visceral punch. As with so much else in Reeder’s overstuffed but underpowered third feature, the oral hemorrhaging is a fetishized detail that seems to have come unstuck from what it might mean. Is it vampirism? Lycanthropy? Psychokinesis? Acute gingivitis? Who’s to say, and, more to the point, why to care?

Streetsmart Jonny (Kiah McKiernan) is a wild child, all right, but a pretty responsible one. When we first meet her, she’s picking a lock in order to carry out a burglary, but the wad of cash she gets from fencing the stolen goods goes straight to her father to cover the rent. Still, despite her usefulness, and perhaps because of the strange ailment he suffers from that occasionally makes his face dissolve into pixellated putty in the bathroom mirror, Dad sends Jonny away to live with her wealthy, frosty maternal aunt Hildie (Alicia Silverstone). After a few sneering, cryptic exchanges between the mulish Jonny and the evasive Hildie, including an 18th birthday celebration that doubles as a ritual to summon the young woman’s ill-defined latent paranormal powers, Jonny enrolls in her new school. 

There she discovers, amid clique politics and active shooter drills run as pass/fail tests (“My parents are going to slaughter me for getting killed,” sighs one unlucky schoolgirl), that something very seedy is going on involving the recent disappearance of several local girls. All of them had dated Kirk (Sasha Kusnetsov), the clean-cut son of the sinister local police chief. So when Kirk shows an interest in Jonny, despite her own romantic inclinations being directed at schoolmate Elektra (Ireon Roach), Jonny hits on a plan to do what parents, school authorities and law enforcement have apparently been unable to do, and unmask the psycho in their midst. Literally — the guy wears a mask when we glimpse him abducting his victims or looming over them in a makeshift surgery whispering sweet, sadly prophetic nothings like, “This is very bad. But it can always get worse.”

The homages, to “Blue Velvet” and “Heathers” in particular, are so overt they almost come fitted with airquotes. And the tacky-to-the-touch aesthetic is deliberate, and not without its trashy, sleazy pleasures. But at other times the cinematography — by DP Sevdije Kastrati, hitherto best known for the humane naturalism of Kosovan arthouse titles “The Marriage” and “Vera Dreams of the Sea” — doesn’t quite have the courage of its lurid, giallo-inflected convictions. Too often the images, like the strained screenplay, reach for a weirdness they can’t quite grasp, and it’s left to a blast of pop on the soundtrack or the scuzzy, synthy crescendos of Nick Zinner’s score to build the ominous atmosphere a noirish horror pic demands.  

The tonal uncertainty is hardly helped by an arch performance style that too often strays closer to play-acting than acting — an impression enhanced by the disparity in age between much of the principal cast and the teenagers they’re playing. It’s a level of artifice that can be splashy fun in a short format (where Reeder has always flourished) but that starts to grate when stretched out to feature length, where a little character depth would be welcome. In particular there’s the missed opportunity of Silverstone’s casting: In a role too big to be a stunt cameo but too small to undergo any meaningful development beyond some elaborate hairstyling, the “Clueless” star is underused as a vehicle to deliver a surrealist, dark-mirror riff on the genre that her most famous role more or less defined. Nor is she given more than one, thin note to play. Her inexplicably antagonistic interactions with Jonny all come out somewhere between a hiss, a snarl and a sinister purr, yet it’s hard to feel any sense of genuine underlying menace.

Fans of a certain kind of kitsch alt-horror, particularly those spearheading the current drive to reclaim Karyn Kusama’s “Jennifer’s Body” — which could be “Perpetrator”‘s soul(less) sister — as some sort of groundbreaking feminist landmark, may jibe with Reeder’s movie. But in even the few years since her “Knives and Skin” trod similar ground with a little more boldness and cohesion, we’ve had a surge of feminist and queer-themed genre films (Halina Reijn’s “Bodies Bodies Bodies” springs to mind as a recent example) that feel far more persuasively current than “Perpetrator.” Operating at a strange remove from modern reality, it seems to belong more to the teen experience of a couple of decades ago, the very era from which so many of its reference points hail. While the issues Reeder wants to address, about standing in solidarity with women and girls and proudly letting your freak flag fly, are far from irrelevant for the Gen-Z teen, will any such person be able to connect with the disjointed rhythms and throwback riot-grrrl vibe of “Perpetrator”? To quote 90’s philosopher-poet-icon Cher Horowitz: as if.