Anyone who’s familiar with teenage girl culture will recognize these extraordinarily charismatic protagonists: Bespectacled, self-possessed Autumn; competent and confident Aaloni; the more childlike Brittney. But appearances can be deceiving: You don’t have to be a prude to find it slightly shocking when Brittney sees the family swimming pool being prepared for the season and she announces that she’ll soon be out there “with a beer and a blunt.”
It’s even more dismaying when Bethencourt and Hill train their cameras on the girls’ relationships with the (usually older) boys in their lives, their interactions ranging across a toxic spectrum of casual dismissal and disrespect to outright assault.
The most stunning sequence in “Cusp” is set at a party where the soft-spoken Brittney is trying to bring attention to the rape of a member of the group’s social circle; she’s reflexively drowned out, and Hill and Bethencourt underline the loss of her voice both visually and by way of a smart, intuitive sound design. The filmmakers, who discovered their subjects while on a photography trip from Montana to Texas, possess an innate eye for beauty and lyricism, whether in the form of a sensational prairie sunset or their coltishly carefree protagonists. In the finest vérité tradition, they somehow manage to keep a respectful arm’s length while burrowing into what look like the most intimate 2 a.m. moments of their subjects’ sometimes chaotic lives. (If the scene with Brittney is heartbreaking, a later moment involving an Only Fans-like site triggers unalloyed terror.)
The adults in “Cusp” are either absent, keeping a somewhat wary distance or, in the case of Aaloni’s mother, trying desperately to keep her connection open by being a “cool mom.” Those efforts might seem cringeworthy or misguided, until their full sobering context becomes clear. “Cusp” exists in a continuum of similarly themed films, from the 2016 documentary “All This Panic” to such narrative features as “Thirteen,” “Mustang” and, more recently, “Cuties.” But Bethencourt and Hill bring their own poetic lens and evenhanded sensibility to a moment in time that, even now, feels fleeting and archaic: In one of the film’s later scenes, Aaloni’s little sister becomes a teenager, signaling the beginning of a new cycle — with even more punitive contours in present-day Texas. In this mesmerizing, revelatory and deeply compassionate film, viewers are left with an indelible impression of girlhood at its most precarious and indomitable.
TV-MA. Available on Showtime. Contains profanity, drug use and sexual situations. 83 minutes.