Peachum is Macheath’s antagonist, the character who opposes the hero and sets the plot in motion. Self-interest motivates Peachum throughout The Threepenny Opera. His only concern is making a profit with his business. Throughout the play, Peachum does not change. He never sways from trying to keep what is his. However, when the queen frees Macheath at the end of the play, Peachum gives up and accepts defeat. This moment of defeat is the only instance in which Peachum experiences a change within himself.
Peachum is an ironic villain. Traditionally, the villain would pursue evil essentially for the sake of evil. He would be someone who does horrible things because he is innately bad. This kind of villain actually reinforces traditional moral positions by making the audience see how awful a person is without them. Peachum, however, is the play’s strongest advocate of traditional morality. He obeys the law, reads the Bible, and wants his daughter to respect her parents. Yet he reads the Bible and obeys the law only because he thinks these activities will aide his business, not because he desires to be a noble citizen. Peachum’s use of traditional morality to justify his cruelty is a powerful way to emphasize both the arbitrariness of values and hypocrisy of religion.