This propulsive, highly satisfying 2002 documentary concerns a group of daredevil skateboarders from an economically depressed and dangerous area of Santa Monica known as Dogtown who reinvented the sport in the 70s. Known as the Z-Boys—their sponsors were the scruffy owners of the Zephyr Surfboard shop—they took their gravity-defying moves to back alleys, abandoned swimming pools, and the asphalt-and-concrete berms around their high schools, where they scandalized their more earthbound 60s-style competitors. Erstwhile Z-Boy Stacy Peralta incorporates interviews with the grown-up boarders, and his accomplished (if occasionally overcut) film combines nostalgia for the group’s artistry with a poignant examination of the inevitable loss of innocence: lucrative deals with skateboard manufacturers swiftly broke the group apart. 89 min.