The Three-Act Structure, or the Paradigm Structure, is the most widely used screenplay structure. Syd Field made this famous in the late 1970s book Screenplay: The Foundations of Screenwriting. Using Aristotle’s concepts in Poetics, Syd Field postulated that most screenplays have a beginning, a middle, and an end.

Each act can have multiple plot points or events that move the story forward. For example, for the beginning or act one, usually between 25 to 30 pages, we have two main plot points: the Inciting Incident and the Key Incident, or Plot Point 1.

Inciting Incident: This event sets up the story and presents a problem affecting the protagonist. It occurs 10 minutes into the script.

Key Incident (Plot Point 1): This event shows what the story is about and happens at the end of the first act.

In the first act get your principal character up a tree; in the second act, throw stones at him; in the third, get him down gracefully.

Anonymous

The second act, which usually runs between 50 to 60 pages, has two main events: The Mid Point and Plot Point 2.

The Mid Point: As the name suggests, this event happens in the middle of the script. It usually presents a low point for the protagonist.

Plot Point 2: This event happens at the end of the second act, and the point of no return leads the protagonist to the end of the story.

For the third act, which runs between 25 to 30 pages, there are two main events: The Climax and the Resolution.

The Climax: This is the point where our protagonist either wins or loses their challenge.

The Resolution: This presents our protagonist in their new world.

And that is the Three-Act Structure. Every story has a beginning, a middle, and an end that takes our heroes through their adventures.