Note: Frederick is the abductor, and Miranda is his unwilling prisoner.
The movie chose to omit an entire chapter of the book. It was chapter two, which is comprised of Miranda's journals reflecting on her everyday since her captivity, on her captor and on her family, friends and her crush (love / lover?), all of whom she left behind. In the novel, Frederick narrates most of the plot in chater one, from the beginning to most of Miranda's captive days. Then in chapter two the narrator changes to Miranda reading her journals, which develops her character and provides much-needed extra information. Her journal is parallel to the previous chapter, reflecting on events that took place in chapter one. By chapter three Miranda becomes too sick to write her journals and Frederick again takes over to tell what happens until she unexpectedly dies. Chapter four takes up only three pages and works as the plot twister. It makes good use of irony, because all the way through the novel Frederick never fails to show how much obsession and love he has for her and at the very last three pages he shocks the readers by stalking another girl, as if nothing happened, shortly after Miranda's death. Since chapter two is parallel to the previous chapter with different narrator, the absence of it does not interrupt the story flow. And by omitting it the movie buys enough time to successfully deliver the main story relatively faithful to the novel, but at the same time kills the viewers' chance to fully get to know Miranda, one of the two main characters. Her journals are very valuable in the aspect that it fills a gap that the author intentionally presented. In chapter one, although Frederick lets the readers know his thoughts as well as what he says, he couldn't possibly know what Miranda is thinking at any given instant. She responds to him in various ways and the readers could guess as to what she is thinking but that's as accurate as it gets. Frederick also tries to guess what Miranda has in her mind and narrates in the novel, but I do not think a lot of readers would find his guesswork credible because of his mental state. So her side of the story is missing in chapter one and that's what I call the intentional gap presented by the author. Then chapter two steps in, Miranda pronounces her thoughts through her journals and fills the gap. It is as though someone is deprived of something and he badly wants it. When he finally gets it he feels the release of ecstasy, happy to get his hands on the thing he has been wanting so badly. Chapter one deprives of the readers Miranda's take on the story when the author could've chosen a third-person narration and stated both Frederick's and Miranda's minds. Then chapter two gives the missing piece. The chapter is also important because it not only works as a device of catharsis but reveals a lot of Miranda's characters... (I'll stop here)