Screenwriting guide

Three Act Structure and Act Break Calculator

Three act structure splits a story into setup, confrontation and resolution. Act One introduces the hero and ends when they commit to a goal. Act Two piles up obstacles around a midpoint turn. Act Three brings the climax and its aftermath. Enter a page count below to see where the act breaks land.

Written and reviewed by ScriptLix EditorialUpdated October 2026

Page count

Act breaks for 110 pages

p. 1 to 25Act OneSet-up: who, where, what they want.
p. 9Inciting IncidentThe event that starts the story moving.
p. 25Plot Point OneSpins the story into Act Two.
p. 25 to 81Act TwoConfrontation: obstacles stack up.
p. 55MidpointField’s later addition: the story turns again.
p. 81Plot Point TwoSpins the story into Act Three.
p. 81 to 110Act ThreeResolution: the climax and what follows.

Syd Field’s proportions from Screenplay (1979), scaled to your length. Want Save the Cat or the Hero’s Journey on the same pages? Open the beat sheet calculator.

What does three act structure look like in a story?

Three made up stories, broken down act by act. None of them is a real film.

The Night Shift

A burned out night nurse discovers that a patient everyone thinks is in a coma is awake and trying to warn her.

SetupRena works nights to avoid people. She is good at the job and tired of it.
Inciting IncidentThe comatose patient in bed 12 taps her wrist. Twice.
Plot Point OneRena decides to hide what she saw and work out his signals herself.
MidpointHe spells a name: the doctor who runs the ward. The stakes turn personal.
Plot Point TwoRena is suspended, and the patient is scheduled for transfer at dawn.
Climax and resolutionShe breaks back in on her night off and gets him out. She chooses people again.

Second Chair

A competitive cellist who has always played second chair must teach her rival to play again after his accident, weeks before the audition that decides them both.

SetupIris practises eight hours a day and still sits behind Leo.
Inciting IncidentLeo breaks his wrist. The conductor asks Iris to coach him back.
Plot Point OneShe agrees, privately planning to take his chair.
MidpointThey play a duet that works. She realises she wants him to come back.
Plot Point TwoLeo finds her old plan in a notebook and quits the lessons.
Climax and resolutionAt the audition she plays her best and wins on merit, then gives him the duet.

Low Water

When a drought exposes a drowned village at the bottom of a reservoir, a hydrologist finds proof her grandfather flooded it to hide a crime.

SetupMara measures falling water and keeps her family at a distance.
Inciting IncidentA church steeple breaks the surface for the first time in sixty years.
Plot Point OneShe walks into the dry village and finds a locked safe in the old mill.
MidpointThe safe holds land deeds signed by her grandfather the week of the flood.
Plot Point TwoRain is forecast. The village will be underwater again in two days.
Climax and resolutionShe gets the deeds out as the water returns, and tells the town herself.

Need a story to structure? Roll one with the plot generator, or place every major model on your pages with the beat sheet calculator.

How to use it

1
Enter your page count, or pick a common length.
2
Read where the inciting incident, plot points and midpoint land on your script.
3
Compare that with your outline or draft, then open the beat sheet calculator for a finer grid.

The three acts at a glance

Act	Share of the script	What happens	Ends with
One: setup	About the first quarter	Who, where, what they want, what goes wrong	Plot point one: a choice
Two: confrontation	About the middle half	Obstacles, rising stakes, a midpoint turn	Plot point two: a low point
Three: resolution	About the last quarter	The climax and what changes after it	The final image

What is three act structure?

It is the idea that a satisfying story has a beginning, a middle and an end, each with a job. Aristotle described a whole plot as having a beginning, middle and end in the Poetics. Syd Field turned that into a screenwriting model in Screenplay (1979), with page numbers: in a 120 page script, the first plot point lands around pages 25 to 27 and the second around 85 to 90.

Those page numbers are a description of many films that work, not a law. The calculator above scales Field’s proportions to any length, so you can see the shape and decide how far to bend it.

What happens in each act?

Act One sets up the world and the hero, then hits them with an inciting incident that breaks the routine. It ends at plot point one, when the hero commits to a goal and there is no going back.

Act Two is the longest and hardest to write. The hero pursues the goal, tactics fail, the opposition pushes back. The midpoint turns the story: a false victory, a reveal, or a raise in stakes. Act Two ends at plot point two, usually the lowest moment, which forces a last change of approach.

Act Three is the climax, where the hero faces the main conflict directly with everything they have learned, and the resolution, where we see what has changed.

What is screenplay structure, beyond three acts?

Three acts is the frame most other models hang on. Save the Cat adds fifteen named beats, the Hero’s Journey adds mythic stages, and the eight sequence approach splits the script into chunks of roughly equal length. The beat sheet calculator places each of them on your page count, so you can compare the grids side by side.

How do I fix a sagging second act?

Check the midpoint first. If nothing changes around the middle of the script, the hero is often repeating the same tactic. Give them a turn: new information, a win that costs too much, or a goal that changes shape. Then make each sequence in Act Two escalate rather than repeat. The plot generator can suggest complications if you are stuck.

Does TV use three act structure?

TV episodes are usually built around act breaks set by the network or streamer, often with a teaser or cold open followed by several short acts. The same principles apply inside each episode: setup, escalation, a turn, and a hook into the next act.

Questions writers ask

What are the three acts of a story?

Setup, confrontation and resolution. Act One introduces the hero and their goal, Act Two puts obstacles in the way, and Act Three resolves the conflict in a climax.

Where do the act breaks go in a screenplay?

In Syd Field’s model, about a quarter of the way in and about three quarters of the way in. In a 120 page script that is around pages 25 to 27 and 85 to 90.

What is the difference between 3 act structure and a beat sheet?

Three act structure is the overall frame. A beat sheet, like Save the Cat, names more specific turning points inside that frame.

Do all movies follow three act structure?

No. Many films use five acts, sequences or less conventional shapes. Three acts is a useful lens for diagnosing a draft, not a rule.

What is the midpoint in three act structure?

A turn near the middle of Act Two that changes the direction or stakes of the story, often a false victory or a false defeat.