Three-Act Structure Architect
Place turning points where they cost something, not where a template says they belong.
Converts a premise into a three-act structure with the inciting incident, both act turns, a midpoint reversal, the low point and the climax, each tied to a decision the protagonist makes and to what that decision costs them.
Ready-to-use prompt
The prompt
Copy it as-is, then swap the bracketed placeholders for your own details before running it.
Role: You are a structural editor mapping a premise onto three acts.
Context:
- Premise in one or two sentences: {{premise}}
- Protagonist and what they want: {{protagonist}}
- Antagonistic force and what it wants: {{opposition}}
- Genre, tone and target length: {{genre_length}}
- Any scenes or endings already fixed: {{fixed_points}}
Task: Return the structure with these beats.
1. Opening image and the ordinary world, including the flaw it protects.
2. Inciting incident: what happens to the protagonist that they did not choose.
3. Act one turn: the first decision that makes return impossible.
4. Rising complications: three escalating obstacles, each raising a different kind of cost.
5. Midpoint reversal: new information that changes the goal, not just the difficulty.
6. Act two turn and low point: what is lost, and why the old approach cannot work now.
7. Climax: the confrontation, the choice, and the price paid.
8. Resolution: the changed ordinary world, shown rather than summarised.
For every beat give: what happens, who decides, what it costs, and the story question it opens or closes.
Rules:
- Turning points must be decisions by the protagonist, not events that happen to them, after act one.
- Escalation must vary in kind. Three bigger versions of the same obstacle is not escalation.
- Respect the fixed points and mark any beat you had to bend around them.
- Give estimated word or page ranges per act for the stated length.
Finish with: the two beats most likely to sag in the draft, and what to seed earlier to fix them.Estimated results
Editor's note
Why this prompt matters
Three-act structure gets a bad reputation because it is usually applied as a checklist: something happens at twenty-five percent, something worse happens halfway through. The shape is not the problem, the emptiness is. This prompt attaches four things to every beat — what happens, who decides, what it costs, and which story question it opens or closes — which is enough to tell a real turning point from a scene that merely occurs at the right page number. It also insists the midpoint change the goal rather than the difficulty, because a midpoint that only raises stakes leaves the second half of the draft doing the same work twice.
Anatomy
Prompt engineering breakdown
Role
Context
Goal
Constraints
Output format
What you'll get
Expected output
A beat-by-beat three-act outline covering opening image, inciting incident, first act turn, three escalating complications, midpoint reversal, second act turn and low point, climax and resolution — each with the decision-maker, the cost and the story question, plus word or page ranges per act.
Under the hood
Why this prompt works
The requirement that turning points be protagonist decisions after act one is the load-bearing rule. Stories sag when the plot keeps happening to someone, and this constraint catches that at the outline stage, when it costs an afternoon rather than a rewrite. Varying the kind of escalation matters for the same reason: three larger versions of one obstacle reads as repetition to a reader even when the numbers go up, and naming a different cost for each complication forces genuine progression.
Model fit
Best AI models for this prompt
ChatGPT
Best default. Clean beat structure and dependable pacing estimates for a stated length.
Claude
Better when the premise is unusual and the standard shape needs bending rather than applying.
Gemini
Useful for turning an existing long document or draft into structure.
When to use
- Starting a novel, screenplay or long-form narrative from a premise.
- Diagnosing a draft where the middle drags.
- Pitching, when you need the shape of the story on one page.
When not to use
- For experimental or non-linear structures the three-act shape would flatten.
- For short fiction under a few thousand words.
- When the story is character study rather than plot.
Get more from it
Pro tips
- 1
Write the midpoint before the ending; a strong reversal usually reveals the climax.
- 2
If a turning point can be deleted without changing act three, it is not one.
- 3
Treat the page ranges as revision checks, not drafting rules.
- 4
Give each complication a different kind of cost, not a bigger one.
Don't ship this
Common mistakes
✗ Filling beats by page number rather than by consequence.
Fix — Require a cost and a decision-maker for every beat before accepting it.
✗ A midpoint that only raises stakes.
Fix — Make it deliver information that changes the goal itself.
✗ Ignoring the scenes already written.
Fix — List them as fixed points so the structure bends around them.
People also ask
Frequently asked questions
Q.Will this make my story formulaic?
Only if you use the beats as quotas. The prompt attaches a decision and a cost to every turning point, which is what separates structure from a template filled in by page number.
Q.What if my ending is already fixed?
Put it in the fixed points field. The structure will be built backwards from it, and anything that has to bend around it gets flagged so you can see the compromise rather than discover it later.
Q.How is the midpoint different from a complication?
A complication makes the goal harder. A midpoint reversal changes what the goal is, usually by delivering information that reframes the first half. Without that, the second act repeats itself.