Act I - make sure you got it all

Every story has a beginning, middle and an end – setup, development and resolution. In the setup we’re introduced to the world of the story and the characters that inhabit that world. What is the story about? What is the world like? What time are we in; present, past or future? What is the genre, drama or comedy, mystery or horror, sci-fi or fantasy? Who is your main character and who supports h/her? What is your main character's flaw, what is their goal?

It is very similar to the 7 Questions of Stanislavsky, only at a much bigger scale: the entire story, the world of your script, etc.

In Act One we need to establish the film's world. In many cases that world will be revisited at the end of the story, changed because the events of the story have changed it, for better or worse.

Something must happen to precipitate change - something that motivates the main character to act. The inciting incident, or catalyst, is the call to action. It jump-starts the story’s forward movement.

Also included in the Act One setup is the central question. Also called the dramatic spine or the dramatic premise, everything in the story feeds off the central question, which will ultimately be answered in the third act climax.

The first turning point happens toward the end of the first act and drives us into act two. It is a decision that sets your main character’s goal. It frames the central question and moves the story into act two with new purpose and drive.

The Opening is very important. So much depends on what the eye sees first. A strong image is a strong opening.

It’s also time to introduce your major supporting characters. Supporting characters support the subplots that give dimension to story. The love interest, the best friend, the antagonist - all reveal character and add layers of interest to a story.
Act one is setup – foundation. A story succeeds or fails on the strength of its setup.