One notorious act from vaudeville’s heyday was the Cherry Sisters of Marion, Iowa.  And their claim to fame? They were horrible — so much so to be downright hysterical. As legend has it, their singing, dancing and comedy skits provoked audiences to heckle and even throw vegetables on stage. Now, their story  is part of Actors Theatre of Louisville’s 34th Humana Festival of New American Plays.  It’s told in a musical called “The Cherry Sisters Revisited.” Elizabeth Kramer spoke with playwright Dan O’Brien, who wrote the script. In the photo – Kate Anya Gersten, Renata Friedman, Katie Kreisler and Donna Lynne Champlin.