Owen Gleiberman Chief Film Critic When you sit down to watch a documentary about the Beach Boys, you know what you want: to be immersed in the California dreamin’ of the group’s early surfin’-hit days, in the jaunty beauty of songs like “I Get Around” and “Help Me Rhonda,” and in the story of how Brian Wilson began to figure out a way to turn pop songs into miniature symphonies. You want to be immersed in the recording of “Pet Sounds,” in the Beach Boys’ rivalry with the Beatles, in the derailed masterpiece that was “Smile,” and in how Brian’s mental and emotional problems began to tear himself and the group apart.