Sometimes a person has to know when to say enough is enough. This was the case of Mitch (Karl Malden) in Tennessee Williams' 1947 play A Streetcar Named Desire, which went from stage to screen in 1951 and was directed by Elia Kazan. Mitch put up with a lot things, whether it was from is mother, his friends, or from Blanche (Vivien Leigh).
Mitch was a sweet guy with a mild personality. He let many things roll off his shoulders. When it came to Blanche, he was the perfect gentleman; and he cared for her very much. When Mitch found out that Blanche had been lying to him, he said enough, which is sad because this event changed Mitch; and it was not for the better. A person can take so much before he/she snaps. Mitch snapped, and he almost took it too far.
Blanche had it coming, though. If she had only been honest with Mitch from the beginning, he would have been a little more understanding. Mitch cannot be blamed for the way he reacted when he found out about the lies that Blanche had been feeding him. In fact that he told Blanche that she was too dirty to take home to his mother. Then Mitch basically asked her: "Why buy the cow when you can get the milk for free?" If Blanche had not screamed, Mitch probably would have taken advantage of her.
Mitch was a good guy, but he was tainted by the lies and deceit that he received from Blanche. It is sad to see a character like Mitch destroyed and reduced to nothing by a woman that feels a need to bring everyone around her down because of things that had happened in her life. One should admire a character, such as Mitch, that finally told the world that enough is enough.