The new rock documentary "Mistaken for Strangers" is alternately hilarious, cringe-inducing, inspiring, depressing, stupid and profoundly intelligent. Fans looking to learn something about The National will find that this baffling guerrilla-style film is only tangentially about the band. Its members are in practically every frame, but in a reflection of this navel-gazing post-post-post-modern era we live in, the film is rarely directly about the Brooklyn quintet. Instead, it's a curiously engaging story about family, missed opportunities, achievement, second chances and, ultimately, love. The documentary, which opened in theaters last week and is available on-demand, is directed by Tom Berninger, brother to The National's lead singer, Matt. The band is made up of two sets of brothers - multi-instrumentalists Bryce and Aaron Dessner and rhythm section Scott and Bryan Devendorf - and the elder Berninger, and Matt Berninger saw a kind of symmetry in hiring Tom onto the road crew during The National's "High Violet" world tour. Tom, an amateur filmmaker, had just turned 30 and was living at home with his parents again. He decides to bring his hand-held camera along, and for the most part the band and crew play along with decreasing enthusiasm over several months as the film's theme settles into a rut that could be titled: Why does everybody love my stupid big brother so much? Turns out Tom and Matt, who is nine years older, are complete opposites. Matt is the tall, elegant frontman with droll humor and an ever-present glass of wine who dresses in wool suits and sings delightfully gloomy songs - songs Tom kind of really hates. Tom's a stout guy, into heavy metal acts like AC/DC and Halford, wears his hair shoulder length and his T-shirts black, and often runs through the beer and tequila provided backstage. While Matt gains increasing acclaim with his band, Tom utterly fails as both a filmmaker and a roadie. He's got tons of film, but much of it is filled with bemused band members objecting to questions. And as for his regular duties, he handles them so poorly, he's fired midway through the tour. Tom retreats to Cincinnati and his parents' home where some of the film's most difficult - and honest - moments come when he asks his parents to explain why Matt has so much success where he has none. There are no attempts to spare his feelings, but that doesn't mean there's no love for Tom. Matt soon invites him to Brooklyn where he moves in with Matt, his wife Carin Besser, and their young daughter, Isla. With the help of this new support group and a profound self-awareness, he finishes the film with a sense of pride and belonging. You may not learn much about The National, and that will no doubt turn off some viewers. But you learn something about love and family. In the end the film avoids the tropes of your average rock doc and metamorphoses into something quite moving and beautiful. Not your average rock doc at all.