Tensions build in the apartment throughout the summer. Blanche and Stanley see each other as enemies, and Blanche turns increasingly to alcohol for comfort. Stanley, meanwhile, investigates Blanche's past, and he passes the information about her sexual dalliances on to Mitch. Although Blanche and Mitch had been on track to marry, after he learns the truth, he loses all interest in her. On Blanche's birthday, Mitch stands her up, abandoning her for good. Stanley, meanwhile, caustically presents Blanche with her birthday gift: bus tickets back to Laurel. Blanche is overcome by sickness; she cannot return to Laurel, and Stanley knows it. As Blanche is ill in the bathroom, Stella fights with Stanley over the cruelty of his act. Mid-fight, she tells him to take her to the hospital - the baby is coming.
The next scene takes place weeks later, as Stella and her neighbor Eunice pack Blanche’s bags. Blanche is in the bath, and Stanley plays poker with his buddies in the front room. A doctor will arrive soon to take Blanche to an insane asylum, but Blanche believes she is leaving to join her millionaire. Stella confesses to Eunice that she simply cannot allow herself to believe Blanche’s assertion that Stanley raped her. When Blanche emerges from the bathroom, her deluded talk makes it clear that she has lost her grip on reality.