We meet our heroes, George and Lenny, somewhere in California, on a hot afternoon. It’s 1930s, the years of the Dust Bowl that thrown people to the bottom of poverty. Lennie Small and George Milton are friends on their way to rancho, where some work for them was promised. George, small and sharp-minded, had already made all necessary arrangements about it, so everything they have to do now is to arrive here. They travel on foot and at this moment are tired and hungry, so they stop to have a night rest.
Lennie, big and slow-minded man, is very strong; this makes him a good worker. But he is dangerous in some ways too: his memory is short, his mind is slow and he cannot control his strength completely. Actually he is a child (and not too smart, really) in a body of a big strong man. So, George is not just his friend, but also a sort of caretaker. One more important point about Lenny, that we learn soon: he is very fond of touching soft things. At this moment soft things are represented by a mouse, dead because of too much touching with uncontrolled strength. Several words uttered by George hint at some incident involving a girl in red soft dress that became a reason of loss of their previous job.
George is angry because of it and throws the poor rodent away. This turns Lenny into a child completely, he even tries to retrieve his soft trophy. Later he asks for ketchup for their beans and, when George retorts that there is none, claims that he will go away and live in a cave. Irritated, George makes a remark about the high-quality life that he will live when Lenny will go to the cave. At this Lenny is on a brink of tears and George calms him down by telling many times repeated tale about their future rancho of their own, where they will keep many rabbits and Lenny will tend them. Lenny knows this tale by heart but listens intently – just like a small child would.
Before they fall asleep, George tells Lenny to return to the place where they are staying in case if something bad happens.
In Chapter 2, after our two characters arrive at the rancho, we see a lot of new faces. First of all, the old Candy, a one-handed former shepherd, and his ancient stinky dog. Later the boss shows up and, quite naturally, asks newcomers about their work history, George, who warned Lenny not to speak a word, speaks for them both, cleverly avoiding to mention the incident with a girl and accusation of Lenny in a rape attempt. He just says that their previous work was completed, that’s all. Boss is a little suspicious, because big and strong Lenny keeps silent and George does all the talking. In an attempt to clear it, George says that they are cousins, which is not true. Boss shrugs it away and leaves.
Soon after enters his son, Curly. Here we see a classical “small man type”, he looks permanently irritated and obviously looks for fight. Later, when he leaves after unsuccessful attempt to engage Lenny into fight, Candy explains that Curly is a former light-weight fighter and since then tries to fight with anyone bigger than him. His recent marriage with a woman that is timidly characterized as “tart” did not improve the situation: Curly is obsessed with her, while she – well, she is not. When Candy leaves, George advices Lenny to stay away from Curly, but fight if being touched. The remainder about going to the safe place at the river in case of anything bad happens follows.
Speaking of bad things: Curly’s wife is at the door, pretending that she looks for her husband. Lenny is completely absorbed by her looks, but luckily, one more character arrives. Slim, called “the prince of rancho”, enters and sends the lady away. George gives Lenny another good advice to stay away from this woman. Lenny says that he doesn’t like this place, but George explains that they have to stay here until they’ll raise some money that would allow to buy a piece of land for rancho of their own.
Enters Carlson, another rancho worker. He asks Slim about his dog and a litter of puppies she recently gave birth to. He thinks that Slim can give one of them to Candy, as a replacement to his old stinky dog, because the poor animal deserves be culled; this would stop its sufferings. Lenny overhears them and immediately start to dream about a puppy of his own.
Curly shows up again, looking for his wife. This time he tries to challenge George, but without any success.
In Chapter 3, we learn more about our heroes: George reveals some details in conversation with Slim, a good-natured and clever man. It turns out that George and Lenny are not related at all, that George used to tease Lenny but later changed his attitude, when he discovered some kindness in this slow-minded “cuckoo”. George even tells Slim a real reason of their leaving the previous work: a previously mentioned girl in a red dress was frightened by Lenny’s clumsy attempt to touch her, so she cried rape (and who wouldn’t?). That sent them on the run, and now they are here and Lenny received his puppy.
This talk takes place in a bunkhouse, so no one can be here alone for a long time. Enters Carlson, complaining about the smell of Candy’s dog. He proposes to shoot it with his trusty Luger. Candy is heartbroken, but Slim takes Carlson’s side. The dog is taken outside and not long after a distant shot is heard. Candy lies quietly and turns his face to the wall.
Crook pokes in. This man is tending horses and has a room of his own, but this is not a privilege: he is black and not allowed to live with whites. Crook is worried, because Lenny is hanging out in the barn and petting puppies a little too much. While Slim goes to have a look, Whit, one more ranch worker, engages George into a conversation about Curly and his hypersexual wife. They agree that eventually this woman will cause a trouble. Their talk naturally switches for discussion about local brothels. At this enter Lenny, Carlson and Curley, who is looking for his wife as usual. Upon hearing that Slim is in the barn, he runs there, thinking about a possible adultery. Whit and Carlson follow, eager to see the possible fight. Lenny asks George to tell his usual tale about their future rancho. Candy overhears them and offers his life savings, some 300 dollars, if they would allow him to live with them: he is old but still can be useful. For some time the three are trying to imagine their future.
Everyone come back: Slim and Curly are shouting at each other, Carlson calls Curly a coward, the fighting starts and Lenny is suddenly involved. He does nothing, until George gives him a permission to act at will. The consequences are quite impressive: Lenny seizes Curly’s hand and actually crushes it. Slim, praise him, resolves the situation at once: he offers an “official version” about Curly being injured by a machine, and if he just tries to fire Lenny, everybody will know what really happened. Curly, beaten physically and mentally, agrees. Lenny is scared but George calms him down.
At the beginning of Chapter 4, Crook sits in his room and Lenny comes by. Big fellow feels lonely, because George and others left for brothel, so he came to visit his puppy. Crook’s room is filled with books and bears all signs of a lonely man habitat. Lenny soon tries to engage Crook in conversation and tells him everything about the farm of his dream, rabbits and all. Crook, being not too kind and rather cynical, throws a terrible remark, proposing Lenny to imagine, what will happen, if George would not come back. Lenny is scared and visibly angered by this, so Crook takes his cruel words back and says several sentences about the fact that everybody needs somebody to talk. Enters old Candy, the talk about the farm is resumed, and Crook proposes himself as one more partner: he lives a lonely life and has some savings. The plan becomes much more realistic. While these three discuss their future, Curly’s wife comes: she feels lonely and is ready to talk to anyone who is around. Oblivious of their visible reluctance to talk with her, she asks Lenny about bruises on his face. When Crook interferes, she threatens him to be lynched. George and other return from their happy voyage and Candy tells him about Crook’s participation. George is not too happy about this. A little bit later we learn that Crook is not going to partner up with them: he prefers to leave his life in old habitual way.
Chapter 5 begins with trouble: Lenny has unwillingly killed his puppy. He is completely lost, grieving and fearing about possible George’s reaction. He tries to hide it in hay; he flings it at the wall. In other words, Lenny is desperate, and this is a state in which Curly’s wife finds him. She tries to calm him down, also in a rather crude way, telling him that the it does not matter, there are plenty of puppies in the world. After that, she switches on another subject, telling Lenny that she was supposed to be a movie star, but the world is cruel, and here she is, in a barn, with a simpleton and a dead dog. Lenny tells her that he likes petting something soft. She boasts that her hair is soft, and here is where the trouble starts for real: Lenny tries to pet her and, unable to control his vast strength, eventually breaks her neck. He remembers George’s words about a sage place, where he should run in case of trouble, so he leaves, taking the dead puppy along.
Candy discovers the body of Curly’s wife. He runs to George. Everything is ruined: if Lenny will be caught, Curly will kill him, or the giant would be locked for life. Anyway, there will be no dream farm, that’s for sure. George even tells that he invented this tale, because Lenny liked it, but the reality would be quite different: hard work and money spent for booze and whores. They quickly make a plan, so George returns to the bunkhouse and Candy goes there several minutes later, shouting that he found Curly’s wife dead in a barn. Curly immediately understands who did it and promises to shoot Lenny. While others form a search party, Slim quietly mentions to George, that it was Lenny, beyond any doubt. Curly is fuming, Carlson complains that somebody stole his Luger. George directs the search party in a wrong direction.
In Chapter 6 Lenny is sitting in the safe place, waiting for George. His fear leads to hallucinations of some sort: his sub-consciousness first takes a form of his Aunt Clara and then of a large talking rabbit. Both creatures are scolding him for being bad and never caring about George. Meanwhile, George arrives. His efforts to direct the search party in another direction proved to be useless, they soon will be here. So, he quietly pulls the stolen Luger from his pocket and, after listening to Lenny’s crying, proposes to tell him a tale about the dream farm. He tells Lenny to look at the river and envision everything, including rabbits. Lenny obeys and, by the end of the tale, George shoots him in the head. Lenny’s death is fast and, one can hope, painless. Others come. They are sure that Lenny had Luger and George had to wriggle it our during the fight. Only Slim seems to understand what just happened, so he offer George to go and have some drink, because the man is obviously desperate and heartbroken. Carlson is surprised by George’s reaction.