A few weeks later, Stanley comes home to find that Blanche is soaking in a hot tub, even though it is blistering hot outside. It is Blanche's birthday and Stella has prepared a small party. Stanley makes Stella stop working and listen to him. He has found out something about Blanche. While Blanche is singing "It's Only a Paper Moon," Stanley reveals that Blanche has a notorious reputation in Laurel. She was so wild that the low-class Flamingo Hotel asked her to move out. The army camp close by referred to Blanche as "out-of-bounds" and she was kicked out of her job for being mixed up with a seventeen-year-old boy. Blanche interrupts the conversation by calling for a towel. She notices a strange expression on Stella's face, but Stella assures her that all is well. Stella returns to Stanley and tries to explain that Blanche's early life was fraught with tragedy due to the young boy she had married and that Blanche was never able to recover completely. Stanley isn't interested in such "old history"; he is concerned only with the present.
When Stanley notices the birthday cake, he wonders if company is expected. Stella tells him that Mitch is invited over. Stanley explains that Mitch won't be there tonight because Mitch is an old friend of his and he had to tell Mitch everything that he had found out about Blanche. Stella is shocked and cries out that Blanche thought Mitch was going to marry her. Stanley corrects her by informing her that Mitch is not necessarily through with Blanche but he certainly isn't going to marry her. He also says that he has bought Blanche a bus ticket for next Tuesday and that she has to leave them. Stella protests, but Stanley is firm. He thinks that Blanche's future is "mapped out for her." He then screams for Blanche to come out of the bathroom so he can get in. When Blanche emerges, she notices that something has happened and is frightened.
As Blanche is in the bathroom bathing and singing about the paper moon and make-believe world, the realistic Stanley comes home with a complete case against Blanche. He has collected all the facts and has assembled a list of all the lies that she has told him. Stanley is now ready for his final confrontation with Blanche. He now has all the information he needs to prove again his superiority over her.
Stanley's actions, it must be remembered, stem from several motivations. Most important, Blanche has represented a threat to his marriage. His marital life has not been the same since the arrival of Blanche, and Stanley feels this. Secondly, he is tired of being referred to as vulgar and common. Even if he is vulgar, he feels that his life cannot hold a candle to the type of life Blanche has been leading. Thus he will reestablish his own sense of importance only by proving how degenerate Blanche actually is. Lastly, Stanley is a person who cannot tolerate illusion or make-believe. He is the realist and must have "his cards on the table." Thus, he must, according to his nature, destroy all the illusions Blanche has been creating.
Stanley does not have the sensibility to realize that perhaps Blanche and Mitch could have had a successful marriage in spite of Blanche's past. Instead, he feels some manly obligation to inform Mitch of Blanche's past life. And not only does he tell Mitch, but he buys a bus ticket for Blanche back to Laurel. Note that he could have bought a ticket to another town, but he cruelly buys one that sends her back to the scene of her last failure and the one place where she cannot possibly return.
It is ironic that Blanche is bathing (again symbolic of a cleansing ritual) while all the past that she is trying to wash away is about to be revealed by Stanley.