Macheath, often referred to as "Mack the Knife," is a fictional character from the play The Threepenny Opera by Bertolt Brecht. He is a charming and cunning antihero, known for his criminal activities and romantic escapades. Macheath embodies the themes of corruption and morality, reflecting the struggles of society in a capitalist world. In the story, Macheath navigates a world filled with thieves, beggars, and corrupt officials. His character is a representation of the complexities of human nature, as he is both likable and morally ambiguous. The play critiques social injustices while showcasing Macheath's adventures and relationships.