Harry Potter: 10 Movie Scenes That Are Completely Different In The Books
2. Voldemort Possesses Harry (The Order Of The Phoenix)
In The Book: Following his fight with Dumbledore, Voldemort possesses Harry and goads Dumbledore into killing Harry so as to kill them both. Harry thinks of death and being reunited with Sirius, which expels Voldemort.
In The Film: Voldemort possesses Harry and threatens Dumbledore, but Harry fights him off when he sees his friends, speaking 'You're the weak one,' through his own mouth.
Summary: Again, both versions are great, but the film's visuals work in its favour here, as a montage of Harry's worst memories fade into a montage of his friends and family as he gains the upper hand in his inner battle with Voldemort.
The reason for Voldemort's expulsion from Harry's body is that he doesn't know how to deal with love and friendship, and this is captured in the film scene, whereas the book version needs a later explanation from Dumbledore.