Marlene Dietrich and Leni Riefenstahl, born less than a year apart, lived so close to each other that Riefenstahl could see into Dietrich's Berlin apartment. Coming of age at the dawn of the Weimar Republic, both sought fame in Germany's burgeoning motion picture industry. While Dietrich's depiction of Lola-Lola in The Blue Angel catapulted her to Hollywood stardom, Riefenstahl--who missed out on the part--insinuated herself into Hitler's inner circle to direct groundbreaking if infamous Nazi propaganda films, like Triumph of the Will. Dietrich, who toured tirelessly with...