Disregard the chick-flick implications of the title—Margarita Happy Hour is one tough little movie. Director Ilya Chaiken uses a free-floating structure to nail her chosen milieu—rock ‘n’ roll bohemians on the fringe of the Brooklyn art scene who find themselves saddled with babies as their carefree 20s give way to hand-to-mouth adulthood—with laser-guided precision. At the center of the group of tattooed, leather-pants-clad, bed-head moms is Zelda Moore (Eleanor Hutchins), who has the part-time attentions of daughter Little Z’s daddy, Max (actor-director Larry Fessenden), a one-shot writer who believes that excessive partying and street aggression make him Jack Kerouac and not an irresponsible drunk. Zelda and her girlfriends meet weekly for lurid $2 margaritas to bemoan Medicaid, unpayable bills, and unreliable men as their kids annoy the sleek Sex and the City babes at nearby tables. (“Art school wasn’t a total waste,” one mom says as they combine slushy drinks to make new colors.) These women are strong and self-aware: They lament the passing of their underground party life but acknowledge that they’re moored to responsibility by their children. “We’ve lost the freedom to just die,” says Zelda, before a catalyst enters in the form of Natali (Holly Ramos), a recovering junkie and Zelda’s former lover, who crashes into Zelda’s eight-resident apartment and lends Max a sympathetic ear. The film’s every detail is sharp and uncliched: Zelda changing out of her No. 1 Mom T-shirt before she walks through a party, downtown types awkwardly introducing themselves to Little Z. Hutchins looks like a torn-down Amanda Peet, but her strong jaw and intelligent eyes give her a wry poignancy. And Ramos is extraordinary: Her scratchy-voiced portrayal of a fragile little girl who’s lived too hard recalls Janis Joplin, and her mere presence elicits both sympathy and exasperation. —Arion Berger