Based very loosely on real events — “five and a half percent” true, the opening credits of “Sister Aimee” claim — this unique indie sees a famed faith healer of the 1920s drop off the map to find herself. Anna Margaret Hollyman plays Aimee Semple McPherson, who in real life was a Pentecostal celebrity, known for her huge revival crowds and her forward-thinking use of radio to spread the word.

She disappeared from Santa Monica, Calif., for five weeks in 1926 and popped up in the Mexican desert, claiming to have been kidnapped.

In this adventure from co-directors and writers Samantha Buck and Marie Schlingmann, the showbiz-savvy Sister Aimee loses her zest for the gig and takes off with an aspiring writer (Michael Mosley) hankering to write about Mexican revolutionaries. They enlist a bilingual guide named Rey (Andrea Suarez Paz) to take them over the border via the back roads, as Aimee’s disappearance is national news.

“Sister Aimee” toggles between the road trip and California detectives’ investigation of the healer’s vanishing. The dusty, sweaty aesthetic and supporting cast of first-rate character actors evoke some of the Coen Brothers’ work, but this film has more of a subversive female gaze — especially in the blossoming friendship between Aimee and Rey, who turns out to have her own epic back story. When a musical number materializes out of nowhere, you know you’re in fairly uncharted territory. It’s not without its quirks (and occasional pacing issues), but “Sister Aimee” is a true original — apparently, just like its namesake.