The similarity between the book and the film "Of Mice and Men" is most evident. Even so, there are a few differences, some insignificant and other crucial. However, in the majority of the scenes, the dialogs are taken literally from the book.
The first difference appears in the introduction of the film. The book starts by describing the surrounding landscape of the Salinas Valley where Lennie and George spend the night by the river. We learn that Lennie is mentally challenged and how this affected their stay at the farm where they previously worked. The film starts, however, by showing Lennie and George escaping from this farm and their journey to Salinas Valley.
Another difference that I noticed is concerning Curley's wife. In the book there is a scene where Lennie, Candy and Crooks are gathered in Crooks' room. After a while, Curley's wife emerges and the atmosphere becomes unpleasant.
Crooks finds the courage to stand up against her, and when he does, she verbally breaks him down. In the movie this scene never takes place, and by eliminating this incident Curley's wife's destructive nature stays unrevealed.
The scene where George is about to shoot Lennie is also different in the film than in the book. In the book this episode is long and George has a hard time shooting Lennie. I get the impression that George is hesitating and unsure if this is the right thing to do. In the film the scene is much shorter and George appears considerably more secure . The movie ends with a scene where George and Lennie work together on the little farm that they where planning to buy. This is not in the book at all.
Other scenes that were left out in the movie:The scene where Lennie has hallucinations about...