With October having arrived, movie theaters and streaming services are gearing up — or, given the nature of production schedules, are well prepared — for that most American of pagan holidays, Halloween. 

Not a few people like to be scared, many of them enjoy donning costumes, and probably more than that enjoy an excuse to carouse with friends. A professor at Virginia Tech, Jadrian Wooten, recently reported that more money is spent on Halloween than on the Fourth of July or Super Bowl Sunday. To poach upon the title of a not-so-classic horror film, there’s money to be made in them thar hills that have eyes…. 

An online platform that offers “an unbeatable collection of edge-of-your-seat programming,” Shudder, may appeal primarily to niche tastes, but it’s a subsidiary of entertainment behemoth AMC and affiliated with the Independent Film Channel. The conflation of popcorn appeal and arthouse cred may seem counterintuitive, but horror films haven’t altogether shaken the onus of being disreputable or marginal. 

That is, of course, part of their appeal. If the strictures of genre films are limiting, those limitations can also prompt filmmakers to flex their cinematic ingenuity.

Take, for instance, the Argentinian director Demián Rugna. Mr. Rugna has four feature films to his credit, the best-known of which is “Terrified” (2017), a picture that garnered worldwide distribution and lived up to its overly literal title. Accolades followed: Guillermo del Toro thought enough of the movie to propose an English-language remake. Mr. Rugna’s knack for ambiance and slow-burning rhythms signified a talent both at home with genre conventions and intent on deepening them. Ambitious, but in a quiet way, is Mr. Rugna. 

“Terrified” was, admittedly, a mite fuzzy in character development and cursory in its plot points, attributes that also gainsay his latest effort, “When Evil Lurks.” As audiences gear up for “The Exorcist: Believer,” with Ellen Burstyn reprising her role as Chris McNeil, Mr. Rugna has brought us his own distinctive take on demonic possession. It’s a piece of business as disturbing as it is artful.

A rural township in Argentina is beset by a “rotten,” a malevolent force of otherworldly origin. Seeking to determine what is causing the poisoning of livestock, brothers Pedro and Jimi Yazurlo (respectively, Ezequiel Rodríguez and Demián Salomón) discover that a neighbor, distended to grotesque proportions, is the current host of the demon. With the help of local landowner Ruiz (a my-way-or-the-highway Luis Ziembrowski), Pedro and Jimi dispose of the body in the hopes of ridding the area of its misfortune. 

Alas, Pedro, Jimi, and Ruiz missed the memo on the appropriate protocol for dispensing with a “rotten.” Things go terribly awry. The advice of a “cleaner” — in so many words, an exorcist — is brought to bear on the proceedings and she spends a good minute or two detailing the dos and don’ts required to handle the thing. It’s a pedantic bit of explication and, as such, causes a stitch in the narrative flow. 

Otherwise, Mr. Rugna has crafted a surprisingly picturesque and unflinchingly brutal film that isn’t for the tender of heart. Those who share W.C. Fields’s sentiments about children and dogs will find a friend, of sorts, in Mr. Rugna. You have been warned.

Mention also should be made of “Aberrance,” the first Mongolian film to gain theatrical release in America. If Mr. Rugna is proving himself an auteur, first-time director Baatar Batsukh is an enthusiast. Like the proverbial kid in a candy story, Mr. Batsukh can’t help but indulge his sweet tooth by engaging in all sorts of hyperbolic cinematic flourishes.

Perhaps he felt that his cabin-in-the-woods slasher flick, co-scripted with Erdene Orosoo, needed some music video razzamatazz to get over. All but genre fans will find the results a bit much, but don’t bet against the likelihood of Mr. Batsukh someday directing a film you’ll want to see.

Correction: Rugna is the spelling of the director’s last name. The name was misspelled in some references in an earlier version.