Harbou collaborated with Lang on several more movies -- including his two masterpieces, the silent sci-fi classic Metropolis and 1931's M, the story of an unhinged killer victimizing the children of Berlin -- before the pair parted ways.
After landing in Hollywood, Lang promptly earned plaudits for Fury (1936), an indictment of mob justice starring Spencer Tracy. Although Lang worked in diverse genres, he would remain best known for his gritty thrillers of the 1940s and '50s, including Scarlet Street and The Big Heat, which helped shape the look and feel of film noir. Lang passed away in Los Angeles Aug. 2, 1976.