Porno concerns a group of Christian teens who, while working at a movie theater, conjure an ancient unholy demon by watching a long-buried pornographic movie. So when these kids, in the face of stress or danger, chant their comforting mantra, “CBTL”—short for “Christ Bears the Load”—you can be sure there’s more than one intended meaning.

The feature directorial debut of Keola Racela, Porno, premiering March 9 at the South by Southwest Festival, is a horror-comedy that goes after the devout with knives sharpened. There isn’t a man or woman to be found in this rollicking midnight movie that doesn’t profess to love Jesus, and yet deviant impulses abound, barely kept at bay by forceful proclamations of piousness and condemnations of sin. They may as well be screaming “Get thee behind me Satan!” with every censure of smoking and drinking and sex, even as they covertly harbor untoward impulses they believe will spell their doom.

In one sense, it’s actual curiosity that gets writers Matt Black and Laurence Vannicelli’s colorful characters into trouble. After opening with images of a couple energetically screwing in their home as friends Abe (Evan Daves) and Todd (Larry Saperstein) watch through an open window, Porno brings us into the Beekman Theater. There, Mr. Pike (Bill Phillips) joins his young adult employees—Abe, Todd, goth Chastity (Jillian Mueller) and studly athlete Ricky (Glenn Stott)—in handholding prayer, reminding them that “the Devil dwells just below our feet.” That he does, as the foursome learn, along with flannel-wearing projectionist Jeff (Robbie Tann), once their work is finished for the evening and they get set to enjoy their customary after-hours “movie club.”

The teens’ entertainment options are the two films playing at their establishment during this July 1992 weekend—Encino Man and A League of Their Own—which results in a handful of period-specific jokes about Pauly Shore (“I hear he’s a real cut-up,” opines Todd, wrongly), Sean Astin (who Chastity claims “used to be cute, but he grew up weird”), and Madonna and her then-notorious Sex book. Before the crew can make a final decision, however, they’re visited by a muttering old hobo (Peter Reznikoff) who races around the theater and lobby, in the process revealing—behind a curtain—a boarded-up doorway about which no one previously knew. That leads to a basement where there’s a cobwebby theater and a spooky archive full of old films and books that were destroyed by a fire. Well, not all of them, given that Abe discovers an undamaged canister containing reels that he quickly convinces his cohorts to view.

Much to the shock and horror—and titillation—of Abe and his cohorts, the reels turn out to be a work of evil, filled with images of a buxom nude beauty (Katelyn Pearce) covering herself in blood, a robed man performing a ritual with a curved knife and a mortar and pestle, and lots of glowing paganish symbols flashing across the frame. “Is this an art film?” asks clueless Todd. The answer is, sort of, as the dark arts depicted on screen have been carefully designed to summon the aforementioned cinematic succubus into the earthly realm in all her lewd, lascivious glory. Though Jeff tries to cut this show short, lecturing his colleagues about how “the science of porn” explains that such material sends people into “give me more mode” and “obsession,” the pussy is out of the bag, so to speak, and soon enough, they’re being menaced by the malevolent spirit, which preys upon their weaknesses.

Those are considerable, since everyone in Porno is an upstanding Bible-thumper only on the outside. Abe and Todd are, as we already know, peeping Toms, a pastime that’s landed the latter in local newspapers. Chastity harbors carnal feelings for Ricky, this despite the fact that he claims to have a new girlfriend (“She’s really on fire for God!”) and didn’t write Chastity letters from camp. The reason Ricky was incommunicado, it turns out, is because his summer retreat was held at a facility designed to quell his more Christianity-decried urges. Jeff is a righteous hardcore-loving loudmouth who’s also a reformed nicotine addict and mamma’s boy hiding away from the big, bad secular world. And as for Mr. Pike, let’s just say that the supposedly virtuous manager has a secret of his own locked away in his office.

These and other skeletons come bursting out of the closet—figuratively and literally—during the course of Porno’s ensuing action, which puts its protagonists through a macabre meat grinder of lust, sweat, blood and exploding genitals. It’s a tongue-in-cheek tale in which fundamentalists’ worst fears about sex, pornography and homosexuality are confirmed, and come to arousing life in the form of Pearce’s horned (and horny) monster. Director Racela both validates his characters’ fire-and-brimstone beliefs while simultaneously exposing their spirituality as a flimsy mask used to cover up their true selves. In the face of wanton demonic perversion, the teens are forced to grapple with the fact that, deep down, their strength comes not from religion, but from their inherent nature, no matter whether that jeopardizes their standing in the congregation.

Porno’s playfully amusing critique is woven into the fabric of its plot, although just as integral to the saga’s charms is Racela’s fondness for rubbing his audience’s noses in the shocking, the lurid and the grotesque. Fake-out jump scares materialize early, and once the action kicks into high gear, the filmmaker doesn’t hold back on the (male and female) nudity and bodily fluids, indulging in satanic-ritual nastiness and growling, howling madness.

It’s nothing that hasn’t been done before, in one fashion or another, and there’s a perfunctory quality to the finale that’s somewhat dispiriting after so much entertaining over-the-top hysteria. Still, its cast is populated by affable personalities—in particular Mueller and Tann, the latter of whom has a “heavy metal” rage that’s refreshing to see in such an otherwise pious figure. And it features a particular instance of explosive trauma, and makeshift recovery, that’s so disgusting it’s downright admirable. In that moment, Porno proves as sacredly profane as they come.