In A Streetcar Named Desire, Tennessee Williams juxtaposes concepts of reality and illusion. The main character, Blanche DuBois, comes to stay at her sister’s house to escape her former life and her own fears of aging and of loneliness. She desperately needs romantic illusion. The world of her brother-in-law, Stanley Kowalski, is the world of social realism. This is depicted through the goings-on in their flat and the street they live on but also, even more importantly, through his rough behavior and his opinions. Stanley’s character has a constant need to burst the bubble of illusion that Blanche attempts to build around herself because, in the world he represents, there is no room for hope or delusion. He faces the stark reality of a rough life as a worker who can barely manage to keep his family. For this reason, Stanley is positioned as an antagonist to Blanche.
In a wider sense, Tennessee Williams uses the traditions of the realistic and the romantic drama to underscore the clash between the two concepts. On the one hand, the characterization in the play is detailed and psychologically realistic, and on the other, the sets, which Williams describes in great detail in the stage directions, are symbolic rather than realistic. This device places the viewer in between the two worlds: the realism of hard, unhappy lives, and the highly stylized reflections on Blanche's character and her attempts to shape the world outside to her own desires. The fact that by the end of the play she has a complete breakdown, caused largely by Stanley having raped her, shows in stark contrast how reality crushes the dreamers. In that sense, the denouement of the play is also part of the realist tradition, and the message it sends is hard yet realistic.