History PragmaticAdaptation / LiveActionFilms

* The book version of ''Literature/OneFlewOverTheCuckoosNest'' is narrated by the [[TheVoiceless mute]], mentally ill SupportingProtagonist "Chief" Bromden, so the whole story is [[UnreliableNarrator filtered through his mental illness]]. The [[Film/OneFlewOverTheCuckoosNest film adaptation]] doesn't require a narrator, however, so Bromden is DemotedToExtra, and we see the events of R.P. [[=McMurphy's=]] struggle against the BattleaxeNurse Ratched play out without any of Bromden's warped perspective.

* The book version of ''Literature/OneFlewOverTheCuckoosNest'' is narrated by the [[TheVoiceless mute]], mentally ill SupportingProtagonist "Chief" Bromden, so the whole story is [[UnreliableNarrator filtered through his mental illness]]. The [[Film/OneFlewOverTheCuckoosNest film adaptation]] doesn't require a narrator, however, so Bromden is DemotedToExtra, and we see the events of R.P. [[=McMurphy's=] struggle against the BattleaxeNurse Ratched play out without any of Bromden's warped perspective.

* ''Literature/TheVoyageOfTheDawnTreader'' adds a plotline about the green mist, the "Dark Island", and the swords of the lost Narnian lords in order to turn the novel's string of individual adventures into a more unified storyline. It also seems to be setting up and {{Foreshadowing}} the villain of ''Literature/TheSilverChair'', presumably to better tie an overarching plot together. At this point, however, it seems that a ''Silver Chair'' film is unlikely.

** Peeves doesn't exist anywhere in the movies, whereas he's a recurring character in the books and somewhat so in the games, and so his roles and scenes involving him were either minced or cut entirely.

* ''Film/JurassicPark'':
** ''Literature/JurassicPark'' contained huge chunks of material and detailed exposition about the nature of the dinosaurs, the setup of the park, and the complex interplay of chaotic factors in the environment. It was impossible to include all of this [[Film/JurassicPark in a movie]], so they trimmed it down and presented it in the form of a park orientation cartoon. There are also a large number of exciting incidents that were cut because they added little to the actual plot. In this case, author Creator/MichaelCrichton had a heavy hand in adapting his own novel for the screen.

*** They wanted to cut out house-elf Kreacher from ''Order of the Phoenix'' -- JKR herself stepped in and told them to leave him in. It wouldn't have hurt ''[=OotP=]'' at all, but would've left giant holes in subsequent films (particularly for ''The Deathly Hallows'').

** The novel opened with a mystery about a man's injuries, which are revealed to be from dinosaur attacks. The movie instead opens with a park workers death at the hands of a raptor. Since the book spent a good part of the opening setting up the mystery but was largely disconnected to the rest of the plot, keeping the mystery but making it more directly tied to the plot and characters compared to the book.