Have you ever wondered why there are so many "dumb blonde" jokes--always about women? Or how Ivanhoe's childhood love, the"flaxen Saxon" Rowena, morphed into Marilyn Monroe? Between that season in 1847 when readers encountered Becky Sharp playing the vengeful Clytemnestra--about to plunge a dagger into Agamemnon--and the sunny moment in 1932 when moviegoers watched Clark Gable plunge Jean Harlow's platinum-tressed head into a rain barrel, the playing...