Often times, when a novel is scripted to become a film, a lot of key elements are lost in the adaptation process. Certain parts of the plot are omitted, some explanations are left out, and the suspense built up from characters' inner monologues are lost amongst all the action taking place on screen.
In the novel The Godfather, Johnny Fontane's character is a much larger part of the story than as depicted in the film. The novel discusses his drinking patterns, struggles within the music industry, his ex-wife and children, as well as his problems with women. In the film, he is simply Vito's godson who encounters a problem with director Jack Woltz. Another character who plays a minor role in the film is Lucy Mancini, but in the novel, a large portion of the plot is focused on her relationship with another unnoticed character, Dr. Jules Segal. Dr. Segal is the man who performs surgery on Michael's face, Johnny's throat, and also performs a cosmetic procedure for Lucy.
One of the memorable sayings from the film The Godfather is "going to the mattresses." Viewers of the film understood that it meant going to war, but many of them do not understand why such a saying has that connotation behind it. In the novel it is described as when the families were at war, each family would find an abandoned apartment and lay mattresses all over the floors so that the button men would have a place to sleep.
The scene in which Michael kills Sollozzo and McCluskey is one of the most memorable in the film. In the novel, author Mario Puzo goes into detail about the thoughts racing through Michael's head just before he pulls the trigger. However, in the film, director Francis Ford Coppola opted instead to use audio during this moment. There is the sound of a train which grows louder and louder as the close-up of Michael comes in closer and closer. This was used to simulate the "rattling" of thoughts in Michael's head.
There are two main colors used throughout the film that are prevalent--orange and black. Coppola's use of black was to set the tone of a dark underworld in which the mafia thrived. His use of orange was simply aesthetic. Orange shows up well on black, so Kay had an orange suit, characters eat oranges like crazy, and there are bowls of oranges on almost every coffee table or desk. To the best of my knowledge, Puzo makes little, if at all, reference to the citrus in the novel.
Many of the changes that appear in this film, as well as other films adapted from novels, are to make the film flow better. The novels are often so detailed and lengthy that some elements need to be eliminated in order for the movie not to be too long or so that the focus of certain scene can be directed at the characters rather than minute details.
