Summarized as accurately as possible from Writing Excuses, where it was described by Lou Anders, who himself recounted the version by Dan Decker, whose profession is teaching it to screenplay writers so they can make better films and to film executives so that they know what to look for.
This is not a formula in the way a lot of people think of, as having a negative connotation. They think 'formula Hollywood movies' means the same cheesy things over and over again. What we're really talking about is more of a recipe for Emotional Torque. Hollywood has a formula that has developed over almost 100 years of cinema, basically to get maximum emotional value out of every scene of a film. When you learn the formula, you can use it to shape your own works - regardless of medium - to get that reaction from the audience.
- The Protagonist - the person the story is about. He or she is a person who wants a goal.
- The goal must be something concrete, definable, and achievable. Rather than "I want to be happy" or "I want to be rich", 'I want him to fall in love with me so that I will be happy.' 'I want to win the game show that I'm going to be on so that I will be rich.' 'I want to rob the casino of the guy who's dating my ex-girlfriend, so I can be happy AND rich.'
- The Antagonist - the person who places obstacles to the goal in the path of the protagonist. This does not mean the bad guy. The antagonist's goals are in some way opposed to the protagonist, and they are the one who is blocking the protagonist's journey.
- The Relationship Character - The person who accompanies the protagonist on their journey. Typically, they are someone who has been there, done that before, and they have wisdom to communicate to the protagonist, and the protagonist isn't hearing it.
- The theme of the story, what the protagonist needs to understand in order to succeed, is expressed either by or to the dynamic character. In many cases, this happens as part of an actual conversation. At the end of the story, this conversation or expression of the theme will be revisited, and the protagonist and dynamic character will reconcile with each other.
The story ends when the protagonist achieves or relinquishes his goal, defeats or is defeated by the antagonist, and reconciles with the relationship character. The closer together these things happen, the more emotional impact the story will have.
- First Act (beginning 0% of the way through the story) - introduces the characters and their goals.
- 10%-15% - the protagonist faces a fateful decision. The protagonist is presented with a choice, and how they answer determines whether or not there is a story.
- Second Act (25%) - starts piling on the problems.
- 50% - Up to this point the story has been raising questions. At this point, it begins to answer them.
- Third Act (75%) - the beginning of the third act is the low point - the furthest the protagonist can possibly get from their goal.
- Climax - the protagonist defeats the antagonist, reconciles with the dynamic character, and claims success or failure in his goal.
Three Act Structure is much more malleable than the character roles in this formula; for instance, Die Hard can be analysed as breezing through the first two acts to bring John McClane to his low point as quickly as possible. See also Hero's Journey, which is a similar structure, focused on the plot and its events rather than the characters and their goals.
- Casablanca is the Trope Codifier. After it became a success, screenwriters and film companies started analyzing it to figure out why it worked so well and what they could extrapolate to other films. (This is why the pacing in earlier films can seem odd to modern audiences.)
- Rick Blaine (Bogart) is the protagonist. He wants Ilsa to stay with him, but gives up at the end of the film.
- Louis Renault is the relationship character. His theme is in the line "No, you don't. You're still a patriot."
- Victor Laszlo, hero of Europe, is the antagonist. He wants to flee the Nazis and take Ilsa with him.
- Thelma and Louise
- Thelma is the protagonist. Her goal is to escape, ultimately through suicide.
- Louise is the dynamic character. She and Thelma share the Main role and act as dynamic character to each other.
- Hal Slocumb - the only decent male character in the film - is the antagonist, because he wants to save them from suicide.
- The Dark Knight
- Batman is the protagonist. He wants to not be necessary to Gotham and to retire, and ultimately gives up on his goal.
- The Joker is the dynamic character. "Don't pretend you're like them. You're not like them, even if you'd want to be. You're a freak. Like me!" The reconciliation occurs when Batman answers the Joker's question - "Do you know how I got these scars?" "No, but I know how you'll get these." He tells a joke and accepts his role as the Dark Knight.
- Harvey Dent is the antagonist. He impedes Batman by succumbing to the easy decisions and generally failing to be the white knight for Gotham that Batman wants him to be, even before he becomes Two-Face.