“She’s a complete blank,” the playwright John Guare once said, trying to explain the public fascination with Amanda Knox, the American student accused (along with two men) of murdering her housemate Meredith Kercher during a sex escapade gone awry in Italy. “You can project anything on to her. Is she Henry James’s Daisy Miller, an innocent young girl who goes to Europe for experience? Or is she Louise Brooks, the woman who takes what she wants and destroys everything? Or is she Nancy Drew caught up in Kafka?”