I think I'll start with movies that claim to be based on a book, but you wouldn’t have known if they didn’t have the same title and a few characters with the same name. Blood and Chocolate is the best example of this of which I’m aware. There are parts of the first five minutes if the movie that match the first five pages of the book. A girl, who is actually a werewolf, accidently leads hunters to her family’s house. This leads to the death of some of her family and pack members. Now older, she (Vivian) just wants a "normal" life. She meets a boy named Aiden, they start to fall in love but she can’t tell him her secret and their relationship is causing turmoil amongst the pack. Honestly, if they had changed the title and a couple characters names they would not have had to buy the rights to the book. Vivian’s age, the plot, and the villains are barely similar while the setting and resolution unrecognizable to readers of the book. It was as if they read the first few pages and said, "Right, we can see where this is going, let’s write a script and make a movie"; the problem, of course, is that Blood and Chocolate (the book) does not go where you expect it to go, which is part of what makes it one of my all time favorite novels, especially amongst Young Adult reads.