First, the 16 mm New Wave; then the Super-8 No Wave; and now, an American film movement, based on digital video, with a name that might belong to one of Harry Potter’s friends: It’s Mumblecore! Thriving on the modest truth of clumsy mishaps and incoherent riffs, fueled by a combination of narcissism and diffidence, Mumblecore reflects sensibilities formed by The Real World (our life is a movie) and Seinfeld (constant discourse), as well as The Blair Witch Project (DIY plus Internet). Mumblecore is demographically self-contained. Straight, white, middle class. The movies suggest college, without the course load. There are almost no grown-ups—which is to say anyone over 30. Enter the latest, Hannah, in which recent college grad Hannah (Greta Gerwig) casually breaks up with her boyfriend, has a brief office affair, and then embarks upon another. At one point, she goes on location to the beach; in the big emotional scene, she tearfully confesses to suffering from “chronic dissatisfaction.” Hannah, the third feature by 26-year-old Joe Swanberg, is something like the Mumblecore equivalent of Gone With the Wind