Right up until its premiere at SXSW over the weekend, the plot of the latest feature film from indie darling triple threat Amy Seimetz (she wrote and directed this film, and regularly stars in those by her peers) was kept totally secret—and rightly so. Sun Don’t Shine stars Kate Lyn Sheil (who delighted in a total of four SXSW films this year alone) and Kentucker Audley (who we saw most recently in Joe Swanberg’s Marriage Material) as a couple facing significant obstacles in their dysfunctional relationship.

The places Seimetz took her debut feature from its opening moments of Crystal (Sheil) and Leo (Audley) engaged in a viciously physical argument on a muddy roadside constantly surprised and terrified me. Inspired in part by a reoccurring nightmare Seimetz has been having—that she would one day commit a terrible crime and need to call upon her lover to help her out of her mess—and by the warnings she received as a child growing up in Florida (effectively that young children there are very likely to get kidnapped, their bodies discovered later in the state’s swamplands), the emotional thriller sees the childlike and vulnerable Crystal going along with the plans Leo has set out for them to smooth over their wrongdoings. Audley is exceptional in his performance of the determined Leo, who is ultimately well-intentioned but often cruel and insensitive to his visibly (and audibly) distressed girlfriend—it’s as though he’s playing a heightened version of the distant Andrew from Marriage Material.

The chaotic and vaguely nostalgic tone of the film is thanks, in large part, to cinematographer Jay Keitel, who utilized a borrowed 16mm camera and discount Kodak film—as well as a hazy, hectic, almost drunken handheld shooting style—to best visually illustrate the desperation of our heroes.

Shot in the Florida everglades during 102-degree heat, Sun Don’t Shine is an achievement in low-budget genre filmmaking, bringing depth, engaging and frustrating (read: real) characters to the increasingly stock-standard horror canon. Crystal and Leo are the last two people you’d want to spend extended periods of time in a car with, but I’d happily spend another 80 minutes observing their poor-man’s Bonnie and Clyde frenzy.