Georgina Campbell as Tess in “Barbarian.”

That one-word title looms large over “Barbarian,” one of the most delightfully twisted horror films of 2022, in which a woman named Tess (Georgina Campbell) stumbles into a nightmare when she finds her rental house already occupied by a stranger.

It’s a roller-coaster horror ride filled with suspense, scares, surprising laughs and some of the most delicious cinematic twists since last year’s “Malignant.”

What Tess discovers in the basement leads her into a labyrinth of unimaginable horrors — some closer than you might think. But who’s the real monster in filmmaker Zach Cregger’s Airbnb-of-horrors solo feature debut?

At first, signs point to said handsome stranger, Keith (“It” star Bill Skarsgard, also an executive producer, cannily playing off his Pennywise persona), who turns up the charm to get Tess to lower her guard and spend the night, else brave the storm outside. After a few nice gestures and good conversation, she ignores her instincts and says yes — even as Cregger’s script and Skarsgard’s delivery create a sizzling ambiguity around Keith’s motivations.

Is there something more sinister about Keith that Tess can’t see? Does it have anything to do with the doors that open and close in the middle of the night? The question hangs in the air as Tess makes a series of chilling discoveries in the basement, where a hidden door leads to a shadowy hallway and a secret room where very bad things have clearly occurred.

Beyond lies yet another door leading to the subterranean lair of the film’s apparent titular monster — the volatile Mother.

After introducing Mother, the textbook horror movie monster we expect, Cregger challenges us throughout the film to reconsider who the actual barbarian of the story is. First seen in a Reagan-era flashback, Frank (Richard Brake, who starred recently in Amazon’s “Bingo Hell” and killed Bruce Wayne’s parents in “Batman Begins”) is her inverse — an average suburban family man on the outside and a true monster within.

Borrowing from serial killer films “Angst” (1983) and “Elephant” (both Gus Van Sant’s 2003 feature and the 1983 Alan Clark short of the same name), Cregger builds unease as the camera follows Frank to the store, where he stocks up on a suspicious grocery list, and as he stalks a young woman to her home.

Enter the Hollywood actor AJ, who at first appears to be a ridiculous comedic figure but is revealed to be arguably the scariest character in the film.

As for Tess, it’s her innate sense of empathy — the one that repeatedly sends her toward danger to help others, at her own peril — that helps her understand Mother before she sets them both free.

“She’s someone that is used to traumatic situations and is able to understand how to survive in this situation,” said Campbell. “By the end of the film, I feel like she gets her own agency and is able to get out of the pattern she found herself in again and again and again.”