The Big Uneasy:Trouble the Water goes into the eye of the Hurricane Katrina disaster.

Of the many shorts, features and news video bites devoted to Hurricane Katrina and its devastating effect on New Orleans’ poorest citizens, three titles stand out: Spike Lee’s TV mini-series When the Levees Broke: A Requiem in Four Acts; Dawn Logsdon’s documentary on the Crescent City’s African-American community, Faubourg Treme: The Untold Story of Black New Orleans; and now, Trouble the Water, a documentary that changed direction, like a weather front, in the midst of being made.

Tia Lessin was a producer on three Michael Moore docs as well as on Martin Scorsese’s No Direction Home: Bob Dylan. Carl Deal was an archival producer on two Moore films and has reported from Iraq and Latin America. So when Lessin and Deal saw the first footage coming out of New Orleans after the hurricane slammed the Gulf Coast in August 2005, they knew they had to go there immediately and get the story.

Their original idea was to make a documentary on the National Guard soldiers stationed in New Orleans to keep the peace, but they were denied formal access to the troops. “Fahrenheit 9/11 screwed it up for all you guys,” declared the media liaison. Lessin, Deal and their crew were preparing to shut down the production and volunteer at a local Red Cross shelter when they were approached by Kimberly and Scott Roberts, New Orleans residents with a story to tell. That was a lucky break for everyone, especially us.

Before Katrina, Kimberly, aka Black Kold Madina, was an up-and-coming rapper in the city’s hip-hop scene who had pinned her hopes on a demo CD. Just days before the storm, she bought a hi-8 video camcorder on the street for $20, to record family parties and such. But as the hurricane neared and Kimberly and her husband, Scott, decided to join many of their neighbors in the Lower Ninth Ward in trying to ride out the storm, she began covering the looming disaster herself. Kimberly’s images of people in the path of destruction form the basis of Trouble the Water, in concert with professional production footage, archival shots and broadcast audio. But it’s Kimberly, Scott and their family and friends whose vision rings true. Her Katrina story is among the most amazing pieces of unmediated reality you’ll see this year, or any year.

Kimberly and her family, in common with about half the city’s population, didn’t have the money or wherewithal to evacuate. As the sky clouds up and the barometric pressure drops, she goes out on the street and interviews her neighbors. They’re pretty nonchalant. Most say they’ll tough it out. Then comes the wind and rain, rising water as the levees burst, refuge in the attic as the house fills up, near-panic and prayers, and the heroic efforts of a neighbor, Larry Sims, who carries people on his back to safety at his house. When the rain subsides, Kimberly, Scott and neighbor Brian Noble start the grim task of searching for survivors in the damp wreckage. All this is captured on videotape with Kimberly’s real-time commentary on camera. No other narration is necessary.

As immediate and soul stirring as the visuals are, Trouble the Water’s music track is just as powerful. The filmmakers commissioned a soundtrack score from trip-hoppers Massive Attack, then blended in a funky array of blues, gospel, traditional tunes, second line by the Free Agents Brass Band, and Citizen Cope’s beautiful “Hurricane Waters.” But again, the star of the show is Sister Kimberly Black Kold Madina. She, Scott and Brian relocate to a relative’s home in Memphis, and there she finds the only existing CD copy of her work. She instantly launches into her song “Amazin,’” a truly shattering rap she performs live for the camera in perfect synch with the CD.

Any lingering resentment we might have toward the federal government for its criminal non-response to the Katrina disaster is slowly, quietly replaced by the courage and matter-of-fact steeliness of Kimberly and her friends. They moved back to the Lower Ninth and are now committed to reconstructing their lives and their culture, come what may. Trouble the Water is their inspiring testament, a real-life thriller with a hopeful denouement.

TROUBLE THE WATER (3 ½) Directed by Tia Lessin and Carl Deal. • Starring Kimberly Rivers Roberts and Scott Roberts. • Not rated, 93 min. • At Osio Cinemas.