Tonight's must-see: “American Masters: Walter Cronkite: Witness to History"

A wealth of archival footage accents this genial profile of former "CBS Evening News" anchorman Walter Cronkite, which also serves as a look at TV news history. The episode highlights Cronkite's coverage of the U.S. space program; his visits to Vietnam and 1968 commentary critical of the war; and the 1968 Democratic National Convention; Insights are provided by Tom Brokaw, David Halberstam, Don Hewitt, Robert MacNeil, Morley Safer, Lesley Stahl and Mike Wallace.

Two more finalist spots are up for grabs as performers compete in the third of four semifinal rounds. Brandy, David Hasselhoff and Piers Morgan are the judges. Regis Philbin hosts.

Chris Brown performs, then two of the final 10 dancers are eliminated from the competition.

The sinking of the cruise liner Andrea Doria on July 25, 1956 is recalled in this gripping installment, which features archival photos of the ship that collided with the ocean liner Stockholm in the waters off the New England coast. Included are comments from the Doria's third mate Eugenio Giannini and second officer Guido Badano, and passengers Dante Gallinari, Jerome Reinert and Pat Mastrincola. Also: legal issues from the accident, which took 52 lives; more than 1,600 were saved.