Stanley is fed up with Blanche's presence and the way it has disrupted his life with Stella in their tiny apartment. He also resents the airs that Blanche puts on.
Stanley investigates Blanche's past in Laurel and discovers she has been lying about her life. She lost Belle Reve long ago, not recently, and moved into a seedy hotel called the Flamingo, where it is implied she worked as a prostitute before being asked to leave. Blanche lost her teaching job because she had an affair with a seventeen-year-old old student. By the time she got to New Orleans she was desperate and out of options. Nevertheless, Stanley cruelly gives her a bus ticket as a birthday gift, even though he knows she has nowhere to go.
Stanley also tells Mitch all about Blanche's sordid history, saying he has to protect his friend. Mitch gives up any idea of marrying Blanche, which was her last hope of salvaging a life, yet wants to have sex with her. Blanche protects herself by screaming "fire" but is not so lucky when Stanley comes home while Stella is in the hospital giving birth. Stanley rapes Blanche, causing her fragile mind to finally snap. At the end of the play, she is taken off to an asylum.
Stanley's crude brutality destroys the fragile, romantic Blanche, caught up in dreams of the past.