In chapter one, we meet Lennie and George. The two men are scrambling to find work after an incident involving a girl with a dress. They talk about their dream farm they strive to one day have together. Lennie mentions he wants to take care of the rabbits.
George and Lennie finally find work on a ranch. They meet a man named Candy who shows them the ropes and the and the boss's son, Curly.
George tells Slim what really happened at their old job and thanks him for giving Lennie a puppy. They then shoot the old dog. Curly tries to hit Lennie, but Lennie accidentally crushes his hand. Slim threatens Curly and says if he tells the truth about what happened to his hand, Slim will tell everyone he tried to hit Lennie.
Lennie meets Crooks as they are left behind. They don't get along. They argue frequently. Curly's wife comes in and mentions she is lonely. She just wants a friend, regardless of who it is. Crooks asks her to leave, but she threatens to have him lynched. The men come back from the brothel.
Lennie is upset that he accidentally killed the dog. Curly's wife comes in and offers to have Lennie pet her hair since it's soft. She starts getting uncomfortable and starts screaming, so Lennie tries to shut her up but accidentally breaks her neck.
Lennie runs away to the river where George told him to go if he was in trouble. Lennie and George talk for a bit, and then George kills him in attempt to protect him from Curly's lynch mob.