Inadvertently fascinating, Ben Steger’s documentary about Humboldt Park’s boozy, irony-saturated adult kickball league gives new meaning to the term “tragically hip.” The hard-partying kickballers are a self-consciously zany crew of thirtysomething hipsters who’ve pushed the principle of extended adolescence about as far as it can go. Some of these low-income hedonists from middle-class backgrounds imagine they’re part of a heroic anticapitalist insurgency, others forthrightly call themselves “fuckups,” but none seems remotely prepared for his impending encounter with the brick wall called middle age. When one of the principal scenesters dies, the league rallies movingly behind his widow, but you have to wonder whether they wouldn’t all be better off channeling their yen for eternal childhood into Star Wars geekdom.