What sort of question is that? Of course they do. Well.. sort of. WGA regulations state that a writer must have written at least 50% of a screenplay to receive a coveted “written by” credit. Under the new regulations, if a writer doubles as a director or producer, the threshold is lowered to 33%, for non-original screenplays.
Is everything a scriptwriter writes their own idea? We wish. Initially, revision notes come from a story editor or other creative executive. Notes can be vague, such as increasing the screen time of a certain character, or as specific as making the tone darker or lighter. The script editing process also involves the removal of scenes that are either incongruous to the story or too expensive to film. The writer actions these notes during the rewrites.
There is however, a variance to what is spoken on set and what is written on the page. How much is improv? It has been mooted that Judd Apatow gives his comedic actors a certain level of freedom during filming. Apparently, about 75% of what’s on the page ends up being shot. The remainder is improvised; a funny line that magically emerges from an actor’s mouth on set. If it’s gold, it stays. This is uncredited writing for the actors.
I often read transcripts of movies written after the movie is completed and compare them to the original screenplays on which they are based.
I also heard that Roberto Orci and Alex Kurtzmann hold half day conferences with stand up comedians to brainstorm the best jokes for a screenplay. It’s amazing how collaborative the writing process is, even if only one writer receives the “written by ” credit. We can’t come up with all the best gags and punchlines.
It is common for a film studio to farm out a project to several writers before deciding on the final writer. Considerations were variations in plot, thematic emphasis, tone, dialogue and characterizations. During the rewriting process, it is common to include the best parts from the other participating writers to form a hybrid script.
It is common to add writers who specialize in jokes or other aspects of a script. For instance, Simon Kinberg was hired on “Sherlock Holmes” to write additional action sequences.
Jonah Hill was once quoted as saying that improvisation comes from the perspective of character, rather than jokes. Every method actor knows that during scene study, the scene en mese is determined. A film set can be a magical place, where great lines come from out of nowhere.
A film script is an organic, living, breathing animal that is never truly completed until the final cut of the movie.
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