Steinbeck's short novel follows two men, George and Lennie, as they take on a new job working on a ranch in central California "bucking barley" for the ranch owner and his son.
George and Lennie begin the story at the Salinas River where they discuss their past (the immediate past and the more distant past), discussing how they have come to be here and where they are going (narrative and character exposition). The men have come from "up north" where Lennie has done something that got the men chased out of town. They are on their way to a ranch where they have been hired as laborers.
The two men arrive at the ranch the following day, begin work, and meet the other characters of the novel. These characters are a mixture of ranch hands and ranch owners. Lennie encounters the boss's son, Curley, and is threatened by him. The men also meet Curley's wife. George predicts that she will bring trouble to them. Lennie feels the threat from both Curley and Curley's wife as well, at one point saying:
“I don’t like this place, George. This ain’t no good place. I wanna get outta here.”
The book progresses through a series of conversations relating to isolation, dreams of financial and social upward movement, and general fear/intimidation. The story reaches its climax after Lennie kills Curley's wife and runs back to the Salinas River.
The story is concluded as George shoots Lennie. The meaning of this ending is one of the more debated and intriguing aspects of the short novel.