Which is Which is a combination comedy and game show.  Sponsored by Old Gold Cigarettes, the game featured famous people from movies, music and radio ... maybe.  Audience members heard a snippet of dialog or music then the contestant guessed if the person behind the curtain was an excellent mimic or the real celebrity.  The contestant wins money if they guess right plus Old Gold donated money to the war effort.

Originally, the show was a summer replacement. Ken Murray was the Master of Ceremonies with Richard Himber and his Orchestra providing the music.  In addition to the regular players, the celebrities also provided entertainment after the reveal.  Murray and the announcer or the guest stars often traded one liners for laughs from the audience.