Differences between Book and Movie *Spoilers*
**Spoilers**
These were the main differences I noticed between the book and the movie. The book is excellent, by the way.
In the book, we have no idea what Dorothy's killer/boyfriends identity is until about halfway. He is never referred to by name.
In the movie, Dorrie's pills are for a stomach ache & then "prenatal vitamins." In the book they were to try to cause an abortion. The 1st set of pills Dorrie agrees to take but they do not work. The 2nd set (which were the arsenic) he convinced her to take but didn't because, at that point, she was so happy with the thought of marrying her boyfriend.
Bud was obsessed with the thought of marrying into money. He'd been obsessed with Kingship Cooper for years (hence, in the movie you see him clutching the Kingship Cooper pamphlets.)
In the book there were 3 sisters- Dorothy, Ellen and Marion. After Dorothy was killed Bud transferred schools and hooked up with Ellen. When she wants to investigate Dorothy's 'suicide' she corresponds with Bud (but we have no idea who this 'Bud' is, presumably a close friend.) She suspects Gordon Gant (a local disc jockey whom she comes to befriend) and Dwight Powell (a soda jerk.)
She faux dates Dwight Powell because she believes him to be the one who killed Dorothy. He convinces her otherwise, just like in the movie. After Bud kills Dwight, Ellen runs upstairs and sees Bud with the gun. He said "I had to follow you to make sure you were safe and Dwight was planning to kill you because you found out about Dorothy but I got the gun from him..." (something like that.) He and Ellen drive off and Ellen wants to go to the police and explain. Bud kills Ellen after telling her the whole story.
Bud then gets with Marion as his last shot of marrying into Kingship Cooper. Gordon Gant comes back into the picture, just before the wedding and exposes Bud. With evidence, Marion and Leo Kingship are convinced. They all drive out to the Cooper mine factory and after a showdown where Bud is forced to admit everything, Bud falls from the catwalk and meets his death.
The book ends with them coming back and Buds mother asking "Where's Bud?"