Rudolf Klein-Rogge (born Friedrich Rudolf Klein) was a German film actor, best-known for playing sinister figures in films in the 1920s and 1930s as well as being a main-stay in director Fritz Lang's Weimar-era films.
He is probably best known in popular culture, particularly to English-speaking audiences, for playing the archetypal mad scientist role of C.
A.
Rotwang in Lang's Metropolis and as the criminal genius Doctor Mabuse.
Klein-Rogge also appeared in several important French films in the late 1920s and early 1930s.