Tonight's must-see: “Celebrity Duets”

Debut: Wayne Brady hosts this competition in which Cheech Marin, Lucy Lawless and other nonmusical celebs are paired with established singers, including Michael Bolton and Smokey Robinson. First up: The eight contestants are introduced, then perform.

Tales grow progressively taller when Cheryl and Jim compete to tell interesting stories about their respective days. Ryan: Mitch Rouse. Andy: Larry Joe Campbell.

The singers perform for Supernova. Brooke Burke and Dave Navarro host.

The History Channel has “Katrina: Send in the Guard” and HBO repeats Spike Lee’s passionate, four-hour “When the Levees Broke.” Sundance follows “Saving Jazz,” with a concert film — “In the Sun: Michael Stipe and Friends” — at 10 p.m. “In His Own Words: Brian Williams on Hurricane Katrina” runs at 11 p.m.