Mullally, known to television audiences as the whiney urbanite Karen on "Will & Grace," can be remembered by theatregoers as Rosemary Pilkington in the 1995 revival of How To Succeed in Business Without Really Trying opposite Matthew Broderick. Her other stage creds include a turn as Marty in the 1994 revival of Grease. The actress is scheduled to interview former "Saturday Night Live" cast member Molly Shannon and Joe's Pub regular Isaac Mizrahi. Comic Bonnie McFarlane will also appear. Prior to the last week's previously scheduled hiatus, actor Bruce Willis and talk show host Regis Philbin headed up the late-night show. Current Ma Rainey's Black Bottom star Whoopi Goldberg served as host March 10. Subsequent guest hosts included actor Vince Vaughn ("Swingers"), singer Elvis Costello and former "Saturday Night Live" comedian Will Ferrell.

For more information on "The Late Show With Dave Letterman," visit www.cbs.com.