Watch Stephen Colbert, James Corden's Playful 'Me & My Shadow' Duet

CBS’ The Late Show and The Late Late Show merged Friday night as Stephen Colbert welcomed James Corden onto the 11:35 p.m. program for a chat and an impromptu musical performance. Both Colbert and Corden have roots in musical theatre, especially the works of Stephen Sondheim, so midway through the interview, the…