What are the five parts of a script?

First you need a story. Then you need a setting -- time and place, a set of characters each with a different passion, and an arc for each. Finally, you need a three-act structure, so that the story is engaging over the duration of the film.

Once you've written the script and finished the first draft, the real work begins. Screenplays that end up on film are always rewritten and some are rewritten many times by many writers.