Freder, the son of Joh, the leader of the city of Metropolis, is enjoying himself in the Pleasure Gardens of the Upper city.The Upper city is the residence of the "Thinkers" of Metropolis - those with vision, but no work ethic. Suddenly, a woman enters with children. The woman's name is Maria, and she and the children are from the Lower city - where the workers who carry out those visions live. "These are your brothers," Maria tells the children, before they are all ushered back down to the machines. Freder is intrigued and follows Maria to the Lower city, where he witnesses a horrible accident resulting in the deaths of several workers. When Joh shows no concern for the workers' well being, Freder returns below and takes the place of worker 11811. After his grueling 10 hour shift, Freder goes with the other workers into the catacombs to hear Maria speak. Maria says that a mediator is coming to ease the relations between the workers of the Lower city and the thinkers of the Upper, and tells them the tragic story of the Tower of Babel. Meanwhile, Joh visits his inventor acquaintace Rotwang, who also lives in the lower city. Rotwang has invented a robot woman who he claims can replace the need for human workers. Joh commands Rotwang to give the robot Maria's appearance, then command the robot to incite a rebellion among the workers. This will give Joh an excuse to use violence agains the workers, and eliminate them altoghether. Rotwang kidnaps Maria, then releases his replica of her into the city. Freder eventually rescues Maria, and the two work to save the children of the Lower city - the false Maria has told the workers to destroy the machine, the malfunction of which causes the Lower city to flood. When the workers realize that their children are quite possibly dead, they turn on Maria and take her to the Upper city, tie her to a stake, and burn her. The false Maria is revealed, but Rotwang tries to kill her as well. After Freder saves her, Maria makes her famous statement: "There can be no understanding between the hands and the brain unless the heart acts as a mediator." Freder joins the hands of Joh and Joseph, the leader of the Lower city, finally bringing peace and understanding to the two groups.