-Movie starts off with a woman running away frightened, and then the scene changes to George and Lennie running away from men on horses, most likely police. They both jump in the water and avoid the men on horses. This did not happen in the book, but foreshadows what George tells Slim later on.
-They both jump on a train, and then exhaustingly crawl to where they sit down. This doesn’t happen in the book.
-The next scene, they’re in town near an employment agency, probably in the market area, and upon Lennie’s request, George says they are going to work on a ranch. This doesn’t happen in the book.
-Lennie only drinks water, he doesn’t put his whole head and hat in the water as described in the book.
-Curley’s wife doesn’t exactly match the description given in the book.
-They don’t meet Slim in the cabin they sleep in, but rather they meet him at dinner.
-Slim never tells Curley to take a sore mule back to the barn and bring back a new one in the book, but it happens in the movie.
-Curley doesn’t have a scene in the book where he is boxing, but it happens in the movie.
-A worker named Mike comes and tells Slim that he wants to switch jobs because he can’t keep up with Lennie. This doesn’t happen in the book.
-The conversation in Crooks’ room with Candy, Lennie, and Crooks isn’t in the movie.
-In the book, Crooks comes in and tells Slim he needs some help with something, and that there’s a big guy playing with the puppies in the barn. This doesn’t happen in the movie.
-Lennie doesn’t hallucinate about his Aunt Clara and the talking rabbit when he runs from the ranch.
-George doesn’t find Lennie in the brush, but in the water near the book. In the book, he finds him kneeling down in the brush.
-George doesn’t hesitate before he shoots Lennie.
-The scene after George kills Lennie where he is explaining to Curley and the rest what happened is completely cut from the movie. Instead, it is replaced and finishes off with