Synopsis: Immanuel Rath (Emil Jannings), an old bachelor, is a professor at the town’s university. When he discovers that some of his pupils often go into a speakeasy, The Blue Angel, to visit a dancer, Lola Lola (Marlene Dietrich), he comes there to confront them. But he is attracted to Lola. The next night he comes again, and does not sleep at home. This causes trouble at work and his life takes a downward spiral.