How do you think it should be divided up? Trilogies are popular, so maybe like this (keeping it vague for those who would avoid spoilers)? Film 1: Beginning of the book until the beginning of exile. This one would probably have the most exposition. Kinda like the first Lord of the Rings film. Film 2: Meeting the Fremen, becoming Muad'Dib, and everything else that happens during this time. Film 3: Rise of Mud'Dib, through the end.