Believing her fiance Gregory has been killed in a shipwreck, Mollie Lovell travels to Italy to make a new life. Promised by adventurer Amilcare Passavente that he will make her the Duchess of Nona, she is befriended by Fiametta, mistress of Cesare Borgia, and becomes unwittingly involved in an assassination plot. Will she pay the ultimate price, or will Gregory, still alive and searching for the woman he loves, arrive in time to save her from the wrath of the enemies who hate Duke Valentino?