Existing fans and students of film will be the main audience for this documentary, which traces Richard Linklater’s journey from freewheeling Gen X indie riffs such as Slacker to the scope and ambition of Boyhood, via the Before trilogy and studio comedies such as School of Rock. Linklater is a likable interviewee, candid about failures and unassuming when it comes to successes. At the very least, this will make you want to revisit his back catalogue. It may even prompt you to pick up a camera and make your own film.