Right now Idina Menzel, LaChanze, Anthony Rapp and the cast of the upcoming Broadway musical, If/Then are on a bus barreling toward Washington, D.C. for their world premiere. Though the stars are probably singing travel songs, sharing snacks or snoozing, we are wide awake obsessively listening to this exclusive snippet from the new Tom Kitt-Brian Yorkey musical's opening number. Rock out with cast member Tyler McGee and star Menzel as they belt "If," then catch them in their pre-Broadway engagement at the National Theatre from November 5 through December 8. Can't make it to D.C.? The show hits Broadway's Richard Rodgers Theatre on March 4. We. Are. So. Excited.