Stanley Kowalski is a central character in Tennessee Williams' play 'A Streetcar Named Desire,' representing the raw, primal force of masculinity and the clash between social classes. He is depicted as a brutish, domineering figure who embodies the post-war American ideal of masculinity, contrasting sharply with the delicate and refined nature of Blanche DuBois, the play's tragic heroine. This conflict drives the narrative and highlights themes of desire, power, and the fragility of human dignity.