Rank nostalgia and 1990s hip-hop alone prop up this cocktail napkin sketch of a movie, the debut film from writer-director Jonah Hill. Sunny Suljic stars as Stevie, a precocious pubescent who escapes his depressing family life in mid-1990s Southern California by glomming on to an older group of skateboarders. Eager to prove himself to his new idols, Stevie mimics their nihilistic behavior, sexual promiscuity and drug and alcohol abuse, and he quickly gains a reputation for recklessness. In between endless skateboarding montages, a few wispy mini-conflicts arise within the group, hurtling everyone towards a symbolic car crash that teaches them all a lesson about friendship for some reason. Mid90s is one of the slightest major releases in recent memory, and although a handful of nice moments point to Hill’s potential, none of the characters are developed beyond a one-sentence outline. The great Katherine Waterston is especially wasted as Stevie’s single mother.