TONIGHT'S MUST-SEE

"Prison Break" season opener, 7 p.m., Fox. As the terrific first season ended, Michael had broken out of prison with his framed brother Linc. Everything else had gone wrong. The escape had grown to include a ragged collection of convicts, some of them fiercely dangerous. A bad guy (T-Bag) lost his hand; a good guy (Westmoreland) lost his life. Tonight, problems build. The biggest problem, however, arrives from the outside. As played by William Fichtner ("Invasion"), Alexander Mahone breaks every recent stereotype of an FBI guy. He's disarmingly calm and clever; he's the one guy who can keep up with Michael's brilliant schemes. The result is compelling television.

OF NOTE

"When the Levees Broke: A Requiem in Four Acts," 6 p.m., HBO; concludes Tuesday. Director Spike Lee has crafted a brilliant documentary. As slow and pensive as an August day in the South, it introduces New Orleans people, then watches Hurricane Katrina unfold. In an unhurried way, it builds a sense of rage. Lee, the son of a jazz musician, makes strong use of music; trumpeter Terence Blanchard, a New Orleans native, adds a perfect score.

"On Native Soil: The Documentary of the 9/11 Commission Report," 7 and 11 p.m., Court TV. This passionate documentary achieves two separate tasks: It celebrates the efforts of the families of 9/11 victims, who insisted a commission be created to learn why the attacks weren't prevented. It also looks at the key findings, pointing to missed clues and miscommunication that span two presidential administrations.