A thought. Not what the screenwriting books tell you about…
If you can find something that really, really, really boils your blood… write about it. It makes it REALLY EASY to get up in the morning to work… or to stay up late at night and work.
It also makes it easier to rewrite. It makes it easier to stick with the project long after an amateur would have given up.
If there is an injustice you want to talk about, a horrid way people behave toward one another, something awful that happened to you in your past… squeeze the poison onto the page. Plus, you feel good when all that toxic slime is out of you and on the page.
Rage is a superb thing for a writer to tap into. I highly recommend digging some up.