 In November of 1923, in a Berlin where a pack of cigarettes costs four million marks and people has lost faith in the present and future days, the alcoholic and unemployed American acrobat Abel Rosenberg (David Carradine) loses his brother Max, who has just committed suicide after feeling depressed for a period. Seeing the modifications in the behavior of people, but without clearly understanding the reasons, Abel moves to the room of his former sister-in-law Manuela Rosenberg (Liv Ullmann), who works in a cabaret in the night and in a whorehouse in the morning. Together, they move to a small apartment near to the clinic of their acquaintance, Professor Hans Vergerus (Heinz Bennent), who gives a job opportunity to Abel in his clinic. While working in the place, Abel discloses the evil truth behind the researches of Hans.