Hollywood has a certain set of standards when it comes to screenplays that you’ll even hear stories of executives and agents tossing scripts just because they found a single spelling error or the writer was audacious enough to use an “oxford comma.”
Nowadays just about every screenplay looks exactly alike unless you’re famous enough to break all the rules, indie enough for no one to care, or foreign enough to realize money is more important than forcing standards on people who aren’t even in Hollywood.
If you think about it, this is kind of insane. Screenplays are supposed to represent a visual medium and if you’re writing about some crazy sci-fi adventure that transcends the very concept of knowledge itself, you’re going to have to be the world’s best wordsmith. But then again, those execs won’t read it because they felt the line spacing was off (even though it wasn’t).
Sometimes as a reader or intern or assistant you’ll receive “supplementary” materials along with a script that can include a cast list, designs, “set photos,” and other more visually appealing documents. These are almost always for Sci-fi or fantasy films from a director/writer/producer/actor/etc., and they paid some designer to put that packet together to make up for the subpar quality of the script. Other times it’s a film that is just looking for more companies to back its production.
In some ways, screenplays are outdated for the medium that it creates but in other ways it allows those who are actually better at writing to shine through those who are just good at appearances. Occasionally you’ll see some youtube link for some song which is fine and a very new change from the way scripts were written even ten years ago. If you read scripts from the 1980’s you’ll really notice how far the rules have lapsed since then.