•
Emil Jannings as Robert Herne, the protagonist. The film follows his life from that of a normal man to that of corrupt dictator over a period of 20 years. •
John Gottowt as Algol, an extraterrestrial, presumably from the planet orbiting
Algol star, who gives Robert Herne a machine that produces unlimited energy. Algol's motivations are not made clear. •
Hans Adalbert Schlettow as Peter Hell, the son of Herne's friend Maria. He lives in the one part of the world over which Herne has no influence. He travels to seek from Herne aid for his country, but Herne denies his request. He returns to his homeland with Herne's daughter Magda. •
Hanna Ralph as Maria Obal, mother of Peter Hell and a former friend of Herne, from before his encounter with Algol. Her influence causes Herne realise what he has become. •
Erna Morena as Yella Ward. •
Ernst Hofmann as Reginald Herne, Robert Herne's son and chosen successor. Despite his father's promises to one day show him the secrets of the machine, he hungers for power and seeks to overthrow his father by means of a coup. •
Gertrude Welcker as Leonore Nissen. •
Käthe Haack as Magda Herne, Robert Herne's daughter. Following her father's refusal to provide aid, she realises the extent of his corruption and leaves with Peter. •
Sebastian Droste as a dancer. ==Production background==