Tia Lessin, Carl Deal, and Kimberly Rivers Roberts

Is New Orleans still there? You had to wonder this year. By late summer, Barack Obama had made it clear he would not run on the question of where the city had gone or might go, despite fate handing him the issue on a silver platter, with the coincidence of the Republican National Convention, a Katrina anniversary, and a new hurricane to worry the builders of federally guaranteed levees. And so the moment passed. Fox canceled its post-disaster New Orleans cop drama K-Ville. Lil Wayne, rapper of the year, could credibly claim, "Take away the football team, the basketball team, and all we got is me to represent New Orleans." And it just wasn't enough.

The problem was that New Orleans had been abandoned long before 2005.

Like other neighborhoods where you don't go, the flooded parts of the city ascended into rap music the worse they got. So the astonishing documentary Trouble the Water, a film that shoots off flares for a discarded population, turns out to be the story of an aspiring rapper. Kimberly Rivers Roberts videotaped her Ninth Ward neighborhood in rising flood water and put down the camera long enough to become something she didn't realize she was: a hero. She sold drugs to get by before the storm, but that was before. In the water, she lost everything, yet saving other people became the kind of experience that makes you realize how little you own and how much you have.

The beauty of the picture is that you get to see this transformation before your eyes. Directors Tia Lessin and Carl Deal follow Roberts back home to reconstruct the events around her riveting and horrifying homemade footage, her movie within the movie, but they let new scenes play out. Roberts holds back nothing, and when she performs the musical version of what we've seen, as Black Kold Madina, it makes 8 Mile and Hustle & Flow feel like the wishful fantasies they were. Trouble the Water isn't just inspirational: It's the spirit itself, caught naked.

Peter S. Scholtes is writing a book about Minnesota hip hop.