Bono; Johnny Galecki; Kings of Leon Musician and humanitarian Bono; from "CBGB" and "The Big Bang Theory", actor Johnny Galecki; musical guests Kings of Leon. Details Casts Title Bono; Johnny Galecki; Kings of Leon Genres Talk Comedy Release Date 2013-09-26 Episode Runtime 01 Hours 03 Minutes Season Number 20 Episode Number 130 Production Companies Worldwide Pants, CBS Entertainment Productions, CBS Productions, CBS Studios David Letterman Self - Host Paul Shaffer Self -Musical Director Alan Kalter Self - Announcer (voice)