Creepy motel rooms make perfect settings for practically any genre. This kind of confined, intimate and claustrophobic environment can elicit laughter, sexual arousal, anxiety and deep introspection, or perhaps all at the same time. HBO’s “Room 104,” the newest project by siblings/writing partners Mark & Jay Duplass (“Togetherness”), focuses on this kind of space not only as an examination of humanity’s sinister, secretive side, but also as a multifaceted showcase of experimental storytelling. It can be the site of a babysitting job gone wrong, a melancholy reunion with the ghost of a loved one or the liberation of two devout Mormon missionaries.

Instead of being one extended bottle episode, “Room 104” explores the interior of its titular motel room through 12 different stories, each of which contain new characters and situations. While the anthological structure is already part of a growing trend in modern TV shows like “American Crime Story” and “Black Mirror,” the concept fits neatly in “Room 104,” especially since so much can happen in one space during the entire span of the show. By delving into darker, more daring thematic territory, the Duplass brothers have expanded their repertoire of more indie comic efforts (2010’s “Cyrus” and 2013’s “Jeff Who Lives At Home”) with a show that is as unpredictable as it is captivating.

The first episode, “Ralphie,” acts as a fine, albeit slight introduction to the series. Melonie Diaz (“Be Kind Rewind”) gives a wonderful performance as Meg, the hapless babysitter who spends the night watching a disturbed young boy named Ralph (Ethan Kent, “Weeds”). Meg grows more suspicious of Ralph when he starts exhibiting unusual behavior that’s bound to make any viewer’s skin crawl.

For the most part, “Ralphie,” written by Mark Duplass, is a suspenseful and terrifying 30 minutes of tension-building psychological horror. But even with smooth direction from Sarah Adina Smith (“Buster’s Mal Heart”), the script struggles to develop the creepy kid/unassuming adult formula into something more profound and novel. Diaz and Kent make their characters believable and at certain points, the episode implies a potentially spooky twist. But when “Ralphie” does finally reach its climax, the strange, confusing ending doesn’t reveal anything interesting, coming off as an undercooked finish to an otherwise anxiety-inducing episode.

Regardless of “Ralphie”’s middling execution, future episodes of “Room 104” seem promising. The rest of the eclectic cast ranges from well-known actors like James Van Der Beek (“Labor Day”), Philip Baker Hall (“Magnolia”), Nat Wolff (“The Intern”) and Mae Whitman (“Parenthood”) to more relative unknowns like Karan Soni (“Safety Not Guaranteed”), Keir Gilchrist (“It’s Kind of a Funny Story”), Sarah Hay (“Black Swan”) and Lily Gladstone (“Certain Women”). The charming gender and age diversity of “Room 104” possesses a kind of intrigue and mystery so beguiling that it would be impossible not to see how their stories unfold.

At its best, “Room 104” invokes the artistic spirit of Alfred Hitchcock and David Lynch, mixing the former’s obsession with voyeurism with the latter’s dark, warped surrealism. At its worst, the show’s plot drags and lulls, and seeing how “Ralphie” turned out, the show is heavily dependent on how well the actors transform the space into a compelling display. But judging from its ambitious premise, “Room 104” feels like it’s saving up for better, more groundbreaking episodes.