Cabaret

In 1931 Berlin, young American Sally Bowles (Liza Minnelli) performs at the Kit Kat Klub. A new British arrival in the city, Brian Roberts (Michael York), moves into the boarding house where Sally lives. A reserved academic and writer, Brian gives English lessons to earn a living while completing his doctorate. Sally tries seducing Brian and suspects he may be gay. Brian tells Sally that on three previous occasions he has tried to have physical relationships with women, all of which failed. They become friends, and Brian witnesses Sally's anarchic, bohemian life in the last days of the German Weimar Republic. Sally and Brian become lovers despite their earlier reservations; they conclude that his previous failures with women were because they were "the wrong three girls".
Sally befriends Maximilian von Heune, a rich playboy baron who takes her and Brian to his country estate; it becomes ambiguous which of the duo Max is seducing. After a sexual experience with Brian, Max loses interest in the two and departs for Argentina. During an argument, when Sally tells Brian that she has been having sex with Max, Brian reveals that he has as well. Brian and Sally later reconcile, and Sally reveals that Max left them money and mockingly compares the sum with what a professional prostitute gets.
Sally learns that she is pregnant, but is unsure of the father. Brian offers to marry her and take her back to his university life in Cambridge. At first they celebrate their resolution to start this new life together, but after a picnic between Sally and Brian in which Brian acts distant and uninterested, Sally starts to doubt continuing with the pregnancy, and is disheartened by the vision of herself as a bored faculty wife washing dirty diapers. Ultimately she has an abortion, without informing Brian in advance. When he confronts her, she shares her fears and the two reach an understanding. Brian departs for England and Sally continues her life in Berlin, embedding herself in the Kit Kat Club, but the final shot shows men in Nazi uniforms in the front row of the club, intimating that its days are numbered.
A subplot concerns Fritz Wendel (Fritz Wepper), a German Jew passing as a Christian, who is in love with Natalia Landauer (Marisa Berenson), a wealthy German Jewish heiress who holds him in contempt and suspects his motives. The worldly Sally gives advice which eventually enables Fritz to win her love. However, in order to get her parents' consent for their marriage, Fritz must reveal his true religious and ethnic background â a highly dangerous act considering what is in store for Jews under the coming Nazi regime. Even while the Nazis are not yet in power, one night some of them kill Natalia's beloved dog â a small intimation of very much worse to come.
The Nazis' violent rise is a powerful, ever-present undercurrent in the film. Their progress can be tracked through the characters' changing actions and attitudes. While in the beginning of the film National Socialist members are sometimes harassed and even kicked out of the Kit Kat Klub, the final shot of the film shows the cabaret's audience is dominated by Nazi party members. The rise of the Nazis is also dramatically demonstrated in the rural beer garden scene. In a sunlit outdoor setting a boy â only his face seen â sings to a relaxed audience of all ages what at first seem innocent lyrics ("Tomorrow Belongs To Me") about the beauties of nature and youth. The camera shifts to show that the singer is wearing a brown Hitler Youth uniform. He lifts his hand in the Nazi salute as the accompanying music becomes strident. One by one, nearly all the adults and young people watching are caught up in the hysteria and rise to join in the singing and saluting. Max and Brian return to their car after witnessing this show of growing support for the Nazis, Brian asking Max "Do you still think you can control them?". Later, Brian's one-man confrontation with Nazis in the street is a brave but futile gesture, leading to nothing but his being beaten up.
While he does not play a role in the main plot, the âMaster of Ceremoniesâ (Joel Grey) serves in the role of storyteller throughout the film. His surface demeanor is one of benevolence and hospitality ("Willkommen"), his intermittent songs in the Kit Kat Klub are increasingly risque and pointedly mock the Nazis â especially the one where he pretends to be in love with a female ape and sings "If you could see her through my eyes, she wouldn't look Jewish at all".... In a scene when Sally experiences delirium, the Master of Ceremonies is seen holding her breasts â the significance of this is never explained, and it is not clear if it is memory or fantasy.
Although the songs throughout the film allude to and advance the narrative, every song except "Tomorrow Belongs to Me" is executed in the context of a Kit Kat Klub performance. The voice heard on the radio reading the news throughout the film in German was that of Associate Producer Harold Nebenzal, whose father Seymour Nebenzahl made such notable Weimar films such as M (1931), Testament of Dr. Mabuse (1933), and Threepenny Opera (1931).

Question: What does Fritz have to do to get Sally's parents to consent to their marriage?
Answer: He has to revel his true religion and ethnic background.