Richardson, who is making his Broadway debut as Billy Flynn in the Tony winning musical, will join co-host Kelly Ripa for the Thursday, Jan. 23 broadcast of the award-winning talk show. "Live with Regis and Kelly" airs on WABC-TV at 9 AM ET. Check local listings. Richardson succeeds Billy Zane in the role of super-smooth lawyer Billy Flynn. Zane's last performance in the Kander and Ebb musical is scheduled for Jan. 19. Richardson will play the role at the Shubert Theatre through Jan. 26 and will move with the company to the Ambassador Theatre on Jan. 29. He is scheduled to stay with the production through March 9.

A member of the Backstreet Boys group, whose record sales number 71 million, Richardson has performed in regional theatrical productions. Richardson follows another boy band star, 'N Sync's Joey Fatone, who made his Main Stem bow on Aug. 5 in Jonathan Larson's Rent.

Chicago, at the Shubert Theatre (225 West 44th Street), won the Tony for Best Revival of a Musical in 1997 as well as awards for actors Bebe Neuwirth and James Naughton, director Walter Bobbie, lighting designer Ken Billington and choreographer Ann Reinking. The original production was directed and choreographed by the late Bob Fosse. For ticket information, call (212) 239-6200.