"The Blue Angel" deals with the humiliation and breakdown an inhibited, overbearing, sexually-repressed instructor at a boys' prep school. Professor Immanuel Rath discovers some of his students passing round seductive photographs of a sexy cabaret singer. His best pupil confesses that Lola Lola sings and dances at the "Blue Angel," a variety club near the docks. Rath visits the club that night to put a stop to this indecency, but is entranced by his first glimpse of Dietrich straddling a chair crooning "Falling in Love Again" in top hat, stockings, and bare thighs. Rath's self-righteousness cannot survive the seductive voice of the siren. Three of Rath's pupils are watching from the dark, though they duck out of sight of their teacher. Rath decides to corner Lola for "misleading" his pupils while she is in the dressing room preparing for her next appearance. They spend the night together; for the first time in his life, he arrives late for school the next morning to find his class in an uproar. When the principal shows up to investigate the goings-on, Rath leaves his job and marries Lola. The mismatched couple enjoy themselves until they have spent every cent of Rath's bank account. Consumed by desire and tormented by his rigid propriety, Rath's morality degenerates. Lola finally forces him to return to his home town and appear as a clown there. The performance ends scandalously. Lola leaves him for another man. A broken old man unable to bear the humiliation any longer, Rath returns to his old classroom and falls dead on the floor.