Freder
Freder is the son of Joh Frederson, who is the ruler of Metropolis. He has spent most of his time in the Club of the Sons until Maria comes into his life and throws his privilege into relief. He falls in love with her instantly and is radicalized by her message of equality. An idealistic and politically-engaged young man, he is the person who can end conflicts between the rulers and the workers. He is bright-eyed and earnest and at times naive, but these qualities lead him to work towards enacting real political change and helping his society.
Maria
Maria is a member of the working class and a maternal figure for many of the children in the workers' city. She is seen by the workers as a kind of prophet and holds sermons in the underground city about the importance of uniting the ruling class with the working class. She brings a group of the children up to the Club of the Sons claiming, "These are your brothers" early in the film. Later on, she falls in love with Freder, who is her most ardent admirer, and whom she recognizes as the "heart" that can unite the haves with the have-nots. She is gentle, ethical, politically idealistic, and pure of heart.
Joh Fredersen
Joh Fredersen is the head of Metropolis and the leader of the ruling classes. He created the machine that runs Metropolis and ensures that it continues to run, a savvy businessman and imperious leader. He is a very calculating person and seems cold in personality, indifferent to the squalid conditions that so concern his more idealistic son. He expresses his desire to get rid of the working class and replace them with robots. In spite of this, he is also very connected to his son and wants to help him, so ends up hearing what he has to say about the inequality of society.
Rotwang
Rotwang is a reclusive scientist who was once friends with Joh and competed with him for a woman in their youth. He is obsessed with this woman and has a giant statue of her in his house. An inventor, he builds a robot in the likeness of Maria in order to undermine Fredersen's plan and wreak havoc on the city. He is an immoral chaos-loving eccentric who has no regrets about the suffering of others, and acts as the film's chief antagonist.
Thin Man
The Thin Man is Joh's assistant, who spies on Freder and informs Joh when something unusual happens. He is a dark and mysterious character, a cog in the machine of the ruling class.
Josaphat
Josaphat is an assistant employed by Joh, but he is fired early on in the film. Freder, seeing an opportunity, employs Josaphat to be his accomplice in seeking to build unity between the workers' city and the ruling classes. He becomes a loyal and helpful friend to Freder.
Georgy
Georgy is a worker from the workers' city with whom Freder becomes friends.
Robot Maria
The Machine Man is what Rotwang calls his robot. His robot is simply a metallic object at first, but is given the likeness of Maria in a plot to undermine the entire society. Robot Maria is a sexual temptress, a sinful and chaotic entity, tasked with leading the charge towards mass destruction in the city.
