The antagonist of Of Mice and Men is the oppressive society in which migrant workers are kept in fear and isolation. This antagonistic force is embodied by Curley, whose insecurities lead him to lash out at those he deems weaker than himself. When George and Lennie first arrive on the ranch, they begin to absorb its atmosphere of fear and isolation. They agree that the ranch “ain’t no good place,” but have no choice but to stay to earn some money. Curley picks on Lennie, and even though Lennie wins the fight, Slim reminds everyone that Curley still has the power to have him fired or worse.
Because she too has suffered at Curley’s hands, Curley’s wife takes an interest in Lennie, the man who has fought back against the husband she despises. She approaches Lennie when he is alone because she has found that the men won’t talk to her when there’s a chance of Curley finding out. So it is Curley’s bullying that puts Curley’s wife and Lennie alone in a room together. It is also Curley’s bullying that causes Lennie to panic and accidentally kill Curley’s wife. He is frightened that George will be angry that Lennie has ignored his warning to avoid Curley’s wife—a warning that George issued because he fears Curley will hurt Lennie. This fear becomes a reality when George is forced to kill Lennie before Curley can torture and lynch him. In this concluding moment, the power of the land-owning class and American society at large—embodied in Curley—crushes the novel’s protagonists and their dream of owning a farm together.