George tries to take care of his mentally retarded friend, Lennie, whose mental disability makes it impossible for him to judge his powerful strength. Lennie means well and tried hard; he likes soft, furry things, like a mouse and a puppy, both of which he squeezes to death accidentally. Though his great strength is useful on the ranch where he works, his inability to govern his behavior leads him into an accidental homicide. George, not wanting Lennie to live the rest of his life in prison, shoots him in the head as an act of mercy.