Lennie and George reach Salinas River on a hot evening. Lennie was thirsty so he drank from the dirty river. George scolds Lennie for drinking the dirty water. Lennie doesn't remember where they were supposed to be going, Lennie has trouble remembering things. George tells Lennie where they were going once more; George and Lennie were heading to a ranch down south and they were about a quarter mile away. Lennie is not allowed to say anything because he is "special" and if the boss finds out they would not get the job. Lennie has a dead mouse that he strokes in his pocket but George takes it away. It was getting dark and Lennie goes to get firewood so George can cook the cans of beans. Lennie instead goes and gets the mouse and only took "little" firewood. George gets mad at Lennie and throws away the dead mouse. Lennie cries and George tells Lennie that he didn't take it away for meanness. The mouse wasn't fresh and he broke it petting it. Lennie tells George about the lady that gave the mice to him. George tells him that it was his Aunt Clara. George told Lennie to finish getting the firewood, George says how his life might have been without Lennie. He considers how much trouble Lennie gets in. In the last town Lennie was petting a girls dress and she screamed. They were chased out of town. Lennie suggested that he could go away and leave George alone. George says he was "foolin" and didn't want him to leave. He said he would give him a puppy the first chance he got. Lennie wanted George to tell him about their dream. Later George asked Lennie what he was going to do when they meet the boss, Lennie answers "I ain't gonna say a word". Movie link

Slim decided to give Lennie one of the pups because he was going to end up drowning them all anyway. George and Slim were having a conversation. George told Slim about his and Lennie's past. George always messed with Lennie because he was so dumb. George stopped because he told Lennie to jump into the Sacramento River and he did it; but Lennie could not "swim a stroke“(pg.40) and nearly drowned. George also told Slim about the incident that occurred down in Weed.( Lennie grabbed the girls red dress and she took it the wrong way. That got them in trouble with the members of that community and they were chased away.) Carlson came into the room and started complaining about how Candy's old dog smelled. They debated over whether they should kill the dog or not, but finally Carlson convinced Candy to let him shoot the dog. After Carlson shot Candy's dog Candy became quiet and distant. When George and Lennie started talking about their "American Dream", Candy took interest in their conversation. George includes Candy in their American dream because Candy is willing to help pay for it, by giving them the money he gets from his injury and some money that has saved up in the bank. The dream becomes a real possibility. At the end of Chapter 3 Curly and Lennie got into an altercation which then escalates to the point where Lennie ends up crushing Curley's hand.

Lennie is in the barn alone talking to his dead puppy. Then Curley's wife comes in trying to talk to Lennie. Lennie doesn't want to talk to her because he knows he will get in trouble from George. Curley's wife tries to persuade Lonnie to talk to her by saying how she's lonely and how she doesn't have anyone to talk to and Lennie has the other men to talk to. Then she starts telling Lennie about when she was younger she met a man who said she could be an actress but her mother wouldn't let her because she was only 15, But Lennie wasn't listening to her. He was thinking of the puppy he killed and how George wouldn't let him tend the rabbits because of the bad thing that had done. She asks Lennie why he like rabbits so much. He tells her that it is because they are soft and he just likes to pet soft things. At first she thinks he is weird but then she realizes he really isn't and that she likes soft things too. she tells Lennie her hair is soft and is because she brushes it. Then she tells Lennie to feel her hair. He likes how soft it is, so he pets it really hard. she tries to tell him to stop because he is going to mess it up but he keeps doing it. She tries to pull away so he grabs her neck. She starts screaming so he holds her mouth shut. She wont stop screaming which means Lennie begins to get angry. So he shakes her furiously and ends up breaking her neck. When Lennie realizes what he has done he leaves to go to the brush to hide. Later Candy walks in to the barn looking for Lennie but he sees Curley's wife laying there. He thinks she is asleep but then he figures out she is dead. Shortly after George comes in and he finds out that she is dead as well. George and Candy both know that it was Lennie who killed her. Candy finds it hard to believe because Lennie is such a nice guy but George tells him that he didn’t mean to kill her out of meanness it was just an accident. George tells Candy to let the other men know that she is dead while George goes in the bunkhouse( to make it seem like candy just discovered that Curley's wife was dead and that he had nothing to do with it). When the other men get into the room slim walks over to her and checks her pulse then he feels her neck and tells the other men that it is broken. Curley assumed that Lennie had killed his wife and wants to kill him. So Curley tells the other men to get their shotguns and try to find them. Carlson accuses Lennie of having his gun and George tries to defend him saying that maybe Carlson lost his gun. As all the men are leaving to go find Lennie, George tries to stay back and is walking slowly, but Curley tells him to stay with them so no one thinks he had anything to do with her death.