I wrote this screenwriting guide for the blog of the screenwriting software company Arc Studio. Below you’ll find an excerpt from the full guide.

The three-act structure is a story-telling model that can help you write your screenplay. It is loosely defined as a narrative with a beginning, middle, and end. This article will give you an overview before diving into the details of which parts or story beats constitute the three acts. Checklists for each act help you test your screenwriting as you go along.

What Is The Three-Act-Structure?

The three-act-structure is a model that goes all the way back to Aristotle’s dramatic theory as outlined in his work Poetics. In modern times, screenwriting lecturer Syd Field published extensively on the three-act-structure and established it as a paradigm. So what is it?

This narrative model divides the plot of a movie into three sections, which are also called setup or exposition, confrontation, and resolution. They represent the rise and fall of the action and each act is initiated by a preceding plot point. Although there are minor ups and downs or twists during each act, only the plot points turn the story into a completely new direction.

The three acts also place other dynamic incidents throughout the story that are crucial for the development of plot and character, such as the call to action, a false defeat or victory, and the climax.

Why Use The Model Of The Three-Act-Structure For Screenwriting?

You only want to write one story at a time, so it might seem counter-intuitive to break your screenplay into three acts. Yet the most important takeaway from Aristotle’s theory is that the three sections are more than just the beginning, middle and end. It’s fundamental that you connect them to form a unified whole in which each action follows the principle of causality.

The three-act-structure is there to help you place scenes at the exact right moment in order to string your narrative together in a plausible and logical way to create a compelling story with an optimum of suspense and tension thanks to well-spaced twists, turns, and plot points.


Act I sets the stage for the audience with a time and place and an introduction to the most important characters, notably the hero. The action starts with an incident that confronts the hero with an external problem, which is often connected to an internal problem the hero faces as well. The first act therefore poses the dramatic question: how can the hero solve these problems? The premise of your story is that after Act III, the audience will know the answer.

What To Include In Act I

In order to introduce the audience to your story and set up the action in the acts to come, the first act should feature the following:

  • Hero: The protagonist deserves special attention, so you show them in their regular circumstances which they are about to leave.
  • Setup: This is the who, where and when of your story – an introduction of the main and secondary characters and their world.
  • Theme: An allusion to the transformation your protagonist will undergo, a hint what the movie is really about.
  • Call To Action: This inciting incident is the catalyst that will send your hero off into the unknown.
  • Resistance: Your main character shows some reluctance to accept the call and go on their journey.

Opening Image: Painting The Blank Canvas Of The Mind

At the beginning of a movie, the audience’s mind is open as they haven’t yet formed a frame for the story. You can still literally paint anything on this blank canvas and they will accept it. We call this suspension of disbelief. Events of pure luck or chance seem much more plausible in the first than in the second act. Screenwriters know this, yet struggle with it because they think they have to come up with a fantastic hook, an early, exciting scene to grab the audience.

James Bond or Indiana Jones films start this way, but that’s because stunts or chases are par for the course for these heroes. Let your opening image show your hero in their world. Provide a snapshot of their ordinary, everyday life. Ordinary doesn’t mean boring: If your hero hunts space aliens for a living, then you show that.

Hook and opening image don’t have to be the same. You can tease the action and turmoil about to come over your main character, then introduce them in their normal circumstances. At the same time, you can set the mood and tone of the movie with humor or suspense, drama or action, mystery or horror.


It’s important that the audience understands and gets to know your main character before their major change. What kind of person is your hero, with what advantages and flaws? Show the goal your character wants or is pursuing. Any characters that are important in the beginning and for this phase of your main character also need to come into play. To create dynamics between them, the hero usually faces a problem or character flaw, or even more than one. Here, you are setting up the different world of the second act. The audience needs to see that things cannot stay the same for your protagonist. If nothing changes, they will never attain their goal. In screenwriting terms, this is called stasis equals death (literal or figurative).


Your first act plants the seed for what will grow into the theme of your story. Your hero wants one thing but needs another, something that differs from their goal and is universal. By the end of the movie, they will be more independent or responsible, less fearful or selfish, or have found love, faith, forgiveness, trust, or acceptance. It’s up to you to equip your main character with a need that creates a fitting theme for your story. The theme is commonly introduced through a secondary character or thing, not your protagonist. It can be something they see, or a line in dialog with someone else.

Call To Action

Once you’ve introduced your hero with their goal and theme and shown them in their surroundings, it’s time for the call to action. This inciting incident is the catalyst that sets everything in motion. It needs to break the status quo of your main character and prevent them from going back to normal afterwards. This event is an action that happens to the hero; they don’t cause it. In traditional drama, the call to action often comes in the form of bad news. It’s up to you to show something big on screen that your hero will have to face.

Resistance: Should I Stay Or Should I Go?

No character accepts a life-changing event just like that, and neither should your protagonist. They assess the incident and consider their chances, but they are reluctant to go. So either they debate back and forth if they should really go, or the call has to be repeated a second time to make them embark on their journey. Their old life could literally be in shambles, or their peers cast them out. To show the reluctance of your hero, you can again place them in their usual surroundings so the audience will see how the inciting incident affects every aspect of their life. Depending on your story and main character, you can replace the phase of reluctance with one of preparation. Your hero is not yet ready to leave, so they must gather tools or learn skills before they can go.

Act I Checklist

Do you think your first act has everything it needs to create a compelling beginning for your story? Check your screenwriting with these points:


  • Show your hero in their everyday surroundings.
  • Do you have an opening image and/or hook?
  • Is there a hint at how your main character will change?


  • You’ve introduced the secondary character(s).
  • The audience knows your main character’s goal.
  • You’ve shown your hero’s problem or flaw.


  • The theme relates to what your hero will learn or how they will change at the end.
  • A character or thing introduces the theme, not your protagonist.

Call To Action

  • The inciting incident happens to the main character in an action scene.
  • The call to action makes it impossible for your hero to return to normal.
  • The status quo is broken.


  • Your hero ponders a (dramatic) question, i.e. should I stay or go?
  • If your protagonist needs to prepare, what for and why?
  • Your hero is reluctant to follow the call and you show how that affects their life.

Act II: Confrontation

In this part, we’ll address all the necessary elements you need to include in the second act of your story before we deal with common problems that cause screenwriters to get stuck in Act II.

What To Include In Act II

The second act isn’t called confrontation for nothing. This is when you get to throw all sorts of problems and obstacles at your hero. To have enough rising action and a full character arc for your protagonist, you’ll need to include these elements:

  • Crossing The Threshold: Your hero finally decides to accept the call to action. They venture outside of their status quo as outlined in Act I and now face a complete reversal in Act II.
  • B Story Character: A new character comes into focus. They will later help the protagonist to learn the theme. The B Story character can be a friendly helper, a love interest, a mentor, a foe, or even a thing.
  • Fun And Games: In this long stretch, you get to fulfill the audience’s expectations according to genre. Your hero is making progress or fails repeatedly in many action scenes – car chases, explosions, and fights, here we go!
  • Midpoint: story brings a premature victory or defeat for your hero. Either way, you raise the stakes and let the audience know the journey is far from over.
  • External To Internal: Now a trajectory opposite to the one that led up to the midpoint begins for your main character. More and more, they have to face their internal problem(s) before real change is possible.
  • All Is Lost: As the name implies, your protagonist hits rock bottom. Together with their internal struggles, an external event makes them despair.
  • Dark Night Of The Soul: In their darkest hour, your hero reflects on everything that’s happened so far. Can they – will they – go on? If you will, it’s a mini cliffhanger before Act III.

Your main character comes out of Act I after the inciting incident called them into action, yet they resisted; now they finally cross the threshold and embark upon their journey, fully intent on solving the problem they face. But they aren’t ready yet and only find themselves in more trouble. The meat and bones of Act II is a lot of ups and downs until the halfway point, after which your hero will switch gears from the external to the internal journey and begin their transformation before the big finale in Act III.

Crossing The Threshold

Your hero pursues what they want and makes a conscious, proactive choice: the hero’s journey has begun. Adventure can begin with a physical step or a metaphorical one. What’s important is that leaving their surroundings of Act I, the main character finds a world that is the inverse of what they know: Katniss Everdeen enters the Capitol (The Hunger Games), Cooper leaves his family to join NASA (Interstellar), and Forrest starts running (Forrest Gump).

Following Joseph Campbell’s The Hero’s Journey, the protagonist is committed to the quest, which also means they seek to obtain what they think their reward will be. Little do they know things will turn out differently! As an opening of the second act, Crossing The Threshold also sets up the long part of Fun And Games.

B Story Character

In the first act, you introduced secondary characters who are connected to the external story. Now it’s time for a helper figure, the B Story character. Only once they’ve crossed the threshold can the hero notice this person, people, or thing(s). Sure, they can have met before, but now they come into focus. The B Story character will come to play a major role later, but it’s important you introduce them early on in the second act so the audience won’t have the feeling they appear out of nowhere as an instant solution to help your main character fix their flaws or problems.

Fun And Games

Now it’s time to deliver and fulfill the promise of the premise, in other words, give the audience what they want. Trials And Tribulations is another name for this section that makes up the meat of Act II and roughly 30 percent of your movie. In a nutshell, your hero has to try and fail, then do it again and again. Of course, there are many ups and downs along the way, but you either put your protagonist on an upward or downward trajectory, headed for success or failure. This will have consequences for the midpoint and in fact the rest of your second act.


Your story’s pivot point comes roughly in the middle of your script as well as the middle of Act II. The previous path of your hero leads to either a false victory or defeat as a culmination of their trials and tribulations. In the monomyth of The Hero’s Journey, the midpoint is an ordeal, a do-or-die moment.

The purpose is to raise the stakes and begin the shift from external to internal journey. From now on, the hero will have to address the need inside them. A Story and B Story begin to cross. This is when countdowns start, love stories become serious, major plot twists occur, or a public outing makes it impossible for the main character to ever go back to how things were before.

External To Internal

Another name for this part of the second act is Bad Guys Close In: they’ve been foiled and now come back stronger than before after the Midpoint. But your hero’s struggles are not only external, but also internal. The main character still hasn’t changed and is dealing with the same problems or flaws you’ve outlined in Act I.

As for the direction of this shift from external to internal: after a false victory at the Midpoint, your protagonist will now be on a downward path towards rock bottom. If you’re following The Hero’s Journey, at this point the hero gets a reward, which is not yet the thing that will ultimately save them. In the case of a false defeat, you now give them a minor victory. Things seem to look better, just before the All Is Lost.

All Is Lost

Your hero needs another push, this time towards transforming themselves. All Is Lost is another inciting incident before the third act. Something big happens to the main character that takes everything away from them and pushes them into despair. It’s the point in the movie where a mentor or helper character dies or a love interest leaves. Your protagonist is facing their inner demons alone. Note that what’s happening to them is not necessarily their fault, yet their despair has everything to do with them. If your hero had no flaws, they wouldn’t feel so lost.

Dark Night Of The Soul

Remember your hero’s resistance to the call to action at the end of Act I? The Dark Night Of The Soul is the same: your hero is assessing the situation and thinking about giving up. Again, you can use several scenes to show how this affects their life in several areas. But as your main character ponders their past failures, they realize the common denominator. They themselves always stood between them and achieving their goal. To fix that, change is necessary. You set up this epiphany by placing the main character back in the familiar surroundings of Act I, where suddenly they feel alienated and no longer safe as before. The final battle is often fought close to home, but either way, a big change is coming in Act III.

Common Problems Screenwriters Face In The Second Act

Second act problems are the most common ailment that plagues screenwriters. Fear not, we have some fixes for what you might be struggling with in Act II.

Act II Is Boring

Yes, the second act sucks: after a great setup in Act I, you want to get to the finale in Act III as quickly as possible. What’s in between is drudgery with neither glory nor romance. Your hero’s struggles have become your own. They have to exercise will and find the strength to continue. Your job is to show what keeps them from skipping forward. Even if your hero has superpowers, something keeps them from going straight to the final fight. They have to face their own character first, as we all do. If the audience can relate to that, your second act won’t be boring.

What Goes Where

If you don’t know how to begin Act II or have written a bunch of scenes that all seem to come later, you might have a structural weakness. The second act is a chain of events: cause and effect lead from one action to the next. If you can’t write in chronological order, assess each of your scenes. How close is the hero to their goal? How far are they from where they’ve started? What is happening externally and internally? Place the scenes accordingly under one of the story beats in Act II and see how well the end result flows as a narrative.

Weak Story Foundation

It’s common to enter Act II and begin to doubt the strength of your story’s foundation. Assuming your hero is a well-rounded character, you can test the foundation by looking at the Midpoint and work outwards in either direction from there. Remember, the false defeat or victory in the middle informs the hero’s trajectory before and after. From there you check the Threshold and the rock bottom at All Is Lost: your hero needs to be primed for the coming acts in these sections.

My First Act Goes On Forever

If you don’t have a clear break between Act I and II or have a run-on first act on your hands, you might be too busy world-building to kick off your story, or your call to action is not strong enough so your hero remains in the status quo of the first act. Remember that you can continue to add to the world in the second act, and that your first act only needs to include a few essential elements.

Not Thinking Visually

The old adage show don’t tell holds true for Act II. Of course, dialog is a necessary interaction between characters that you can also use to convey information to the audience, but film is behavior: your hero and other characters reveal who they are through their actions. This is especially important in the second act when the hero needs to come to terms with who they are.

My Main Character Isn’t On-Screen

Whose story are you telling? If your protagonist doesn’t have enough scenes in the second act, you might have the wrong hero, or you’ve locked them up in a predicament too early. Only in the All Is Lost should they reach the end of their wit; a false defeat at the Midpoint raises the stakes and makes them continue. Check out Character Creation to learn about a well-rounded main character.

Screenwriting A Series

A horizontal series sustains an arc for your main character(s) across an entire season. Naturally, each episode requires its own story arc with ups and downs, but in the grand order, when does the second act begin and end? Act II makes up the bulk of a movie or series at roughly 50 to 60 percent. As a rule of thumb, Crossing The Threshold occurs at around 20% and the third act begins more or less at around 80% of the total runtime. In a series of ten episodes, your second act would therefore stretch over episodes three to eight.

Act II Checklist

Even if your struggles and problems with the second act were not listed above, you can troubleshoot your script with the following Act II screenwriting checklist:

Crossing The Threshold

  • Your hero leaves the status quo of Act I (if they’re not physically on the move, they at least try something new).
  • There is a clear break between the first and second act, showing your hero enters an inverse world in Act II.
  • Your hero follows what they want and decides to heed the call to action.

B Story Character

  • You introduce a new character (or thing) which represents the theme.
  • It is because of the new world in Act II that your hero takes note of this character.

Fun And Games

  • Even though things go up and down, your hero is headed for success or failure.
  • It’s Fun And Games for the audience: deliver on their (genre) expectations!
  • Continue to show the difference between your hero’s world before and after the call to action.


  • Your hero experiences a false victory or a false defeat which raises the stakes.
  • You set up the shift from external to internal (or A Story to B Story).

External To Internal

  • Your hero’s internal flaws are working against them.
  • The path is now opposite to the one before the midpoint.

All Is Lost

  • Another big inciting incident happens to your hero.
  • Your main character hits rock bottom.
  • You set up your hero’s character transformation.

Dark Night Of The Soul

  • The hero reflects their situation which leads to an epiphany.
  • They must now change and cannot go back to how things were before.

Act III: Resolution

In this final part, we’ll address how to write the climax of your story in the third act as well as other elements you’ll need to include in the last part of your screenplay.

What To Include In Act III

Writing the third act is easy, you simply need to resolve your story, tie up all the loose strings of your subplots, answer the dramatic question raised in Act I and complete the transformation of your main character – and there should be a killer climax in there! Sounds daunting? We’ll coach you through the elements of Act III:

  • The Fix: After their epiphany at the end of Act II, your hero now realizes how they can fix everything, their problems and their character.
  • Finale: This is the big moment to which you’ve been building up all along – the final battle. In the terms of The Hero’s Journey, this is the fight where the hero dies and is resurrected again transformed.
  • Closing Image: A shot that mirrors the opening on your hero, only now you show them as a reborn person after their transformation.

In dialectic terms, the third act is the concluding synthesis of the thesis, the status quo in the first act, and the antithesis, the inversion in the second act. The finale or climax must bring all problems, both external and internal, to their most intense point. For your story’s ending to satisfy the audience, you must answer the dramatic questions raised in an engaging and resonating way.

The Fix

Remember your hero’s epiphany at the end of Act II where they realized that it was their inner struggles holding them back? In a breakthrough moment, they realize how they can overcome that. The Fix represents the acceptance of the hero’s flawed self and a resulting decision towards a solution. You can do this in a single scene that sets up the longer finale.


If Act III is roughly 25 percent of your movie, the finale takes up most of that with nearly 20 percent screen time. It’s essential not to rush to the climax or deliver a simple, predictable win for your hero. The way to achieve this as a screenwriter is through more ups and downs, or rather with another twist. After The Fix, the solution takes shape as a plan, which you can choose to show before the finale or not.

In short, you break the finale down into these steps: the hero gathers their strength or otherwise prepares; the plan is put in motion; a twist reveals the plan as is cannot work; the hero (figuratively) dies and is resurrected; after which they alter the plan to succeed at the end.

In the approach to the climax, your hero prepares by gathering the necessary tools, which depending on your genre can mean weapons, maps, supplies, or information. If they don’t face their last battle alone, they need a team. At this point, your main character makes amends with A Story characters they’ve alienated before. Once the plan is put in motion, the audience and characters hold their breath if they can achieve the impossible. Secondary characters begin to “take one for the team” and drop off, sacrificing either themselves or their chance towards the common goal, another raising of the stakes for the protagonist.

Enter the final surprise or twist: the hero has stepped into a trap or detects an oversight in the plan. This can be a big reveal (Malcom Crowe in The Sixth Sense was dead the whole time!), a dramatic plummet of the winning odds (Mark hears from NASA that the ascent vehicle is too heavy in The Martian), or any other Your Princess Is In Another Castle moment.

What follows must be a reaction by the main character. Once more they assess their situation, however briefly: defeat or giving up are real possibilities. The theme of your story comes into play. What is it that your hero needs to do or realize? They overcome their inner problems and demonstrate their inner change, completing their transformation. Screenwriters also refer to this moment as the touch of the divine. The hero’s realization of their own mortality is a common theme, but so are love, faith, or responsibility. In the terms of The Hero’s Journey, death and resurrection occur. In the final test, the old hero dies, and the new one is born.

At the climax of the finale, the hero triumphs. They’ve altered the plan, put it to use and succeed. The ultimate reward awaits. It’s up to you as a screenwriter to make that reward metaphorical or literal, but let it represent three things: success, change, and proof. The hero has reached the goal (external resolution), become a transformed person (internal resolution), and completed the (only) path that could get them there (resolution of the journey). Tying up all loose ends is also called denouement.

Closing Image

In the first act, you’ve shown the hero in their status quo before the journey, their world before they changed. Now, all the tension from the climax has dissipated. Let the audience see the transformation. For the contrast between before and after, you can use the familiar surroundings of the first act. The classic ending to The Hero’s Journey is the return to home, where things will never be the same again before the hero has come back resurrected.

The Closing Image can be a single scene or a series of scenes, but the mirror effect between Act I and III works best if you dedicate an equal amount of screen time for opening and closing image. In Kramer vs. Kramer, Ted and his son Billy eat breakfast together, same as they did the first morning after Joanna left. The series of Closing Image scenes concludes in the elevator with the doors closing (literally and figuratively), mirroring the day when Joanna walked out on her husband and her old life.

Act III Checklist

Not sure if the conclusion of your screenplay is a complete resolution? Check your screenwriting:

The Fix

  • Your hero learns the theme and makes a decision.
  • The Fix will change the hero the right way.
  • You set up Act III as a synthesis of Act I and Act II.


  • Your finale has ups and downs and isn’t a straightforward race to the finish line.
  • After the twist, your hero demonstrates how they’ve changed.
  • Your external and internal story cross during the finale.
  • You answer the dramatic question(s) posed in Act I.

Closing Image

  • You show (don’t tell!) the completed transformation of your hero.
  • This final image is a mirror of the hero in Act I.
  • The closing image offers indeed closure (or leaves with a cliffhanger).

This is an excerpt from a guide I wrote for the blog of the software Arc Studio.