'Late Show With Stephen Colbert' will debut on Sept. 8

Stephen Colbert will officially kick off his reign as "Late Show" host on Tuesday, Sept. 8, CBS announced.Colbert, who ended his run on "The Colbert Report" in a wacky finale last month, was named David Letterman's replacement this past spring; the legendary late-night host had surprised everyone when he earlier announced his retirement. Letterman's last night at the desk will be on Wednesday, May 20.