In 2006, Spike Lee's sprawling HBO documentary "When the Levees Broke: A Requiem in Four Acts" delivered the definitive look at the destruction wreaked by Hurricane Katrina on the lower class residents of New Orleans. While other investigative reports on the disaster have come and gone, Lee's portrait remains singularly potent, perhaps because the scale of the production allowed him to tell the miserable tale with unparalleled comprehensiveness.