Sitcom Structure – Classic 2-act vs. Modern 3-act Structure


Quite simply, structure is one of the most important elements of your script. It is the glue that holds your story together. Think of structure as how you choose to tell your story. What happens in each scene and what is the order in which it happens? Let me warn you that structure is one of the hardest things to wrap your head around. It takes time, energy, and boatloads of patience. You probably won’t get it right the first time. You may not get it right the second time. Most likely you will need to rework your story several times before everything finally clicks. Don’t get aggravated by this — it is a normal part of the writing process, one that is difficult for even seasoned writers.

I often see new writers work at story structure, get frustrated, and give up. They say, “I couldn’t figure it out and it was taking too much time, so I just did it my way.” This is a colossal mistake. The television industry isn’t Burger King. You can’t have it your way. Structure exists because it works. Those in the industry understand story structure because they live it every day. If your story is structured incorrectly — or worse still not at all — they will hear it in your pitch or read it in your script and they will automatically think of you as a pedestrian writer because you haven’t conquered one of the most fundamental elements of TV writing.


Historically most, if not all, sitcoms were structured in two acts. An act is a series of scenes that tells a story. For multi-cam shows, an act consists of approximately four to seven scenes. Single-cam shows are different. There will be more scenes, as the scenes in these shows tend to be shorter. In classic two-act sitcom structure, the first act is the setup of your story. It’s where you get your character(s) into hot water. The second act is the resolution. It’s where you get your character(s) out of hot water. The acts should be approximately (doesn’t have to be perfect) the same length.

In the middle of your script, there is what is known as an Act Break. A strong Act Break is key to a good story. Think of it as a mini-cliffhanger. Something big must happen. The reason is that traditionally Act Breaks coincide with commercial breaks. Commercial breaks give the audience a chance to veer away from your show. They can (and often do) pick up the remote to see what else is on. But, a good Act Break will, in theory, bring the audience back because they will want to see what happens and how the character(s) get out of hot water.

Today, many shows now use a more modern three-act structure. Yup, you guessed it: an extra Act Break means an extra commercial break which equals extra advertising dollars. To make it easy, you can think of the three acts as the beginning, middle, and end. If you want to dig a little deeper, I like to think of the first act as the set-up, the second act as the heart and soul of the story, and the third act as the resolution. As with two-act structure, each act should be approximately the same length (though in some shows this can vary) and the first and second acts should both end with strong Act Breaks.

Typically, a show is consistently written in two-act structure or three-act structure. In other words, shows don’t usually mix-and-match by doing two-act one week and three-act the next. It is too confusing for an audience.

On occasion, you may see a show that has four Act Breaks. Bob’s Burgers, for example uses four-act structure. Again, this allows for yet another commercial break. This structure is not used frequently with comedies, but that could change, as it has proven to be successful for Fox with Bob’s Burgers, which is obviously a hit show.

When you are writing a spec script or pitching an episode, you should structure your story in whichever format your particular show follows. How can you be sure how many acts your show has? It’s easy. Watch the show for a few weeks when it actually airs. Does the show have one mini-cliffhanger and commercial break that comes about halfway through? Then, obviously, that show is following classic two-act structure. But, if the show has two mini-cliffhangers and two commercial breaks, then the show is following the more modern three-act structure. A word to the wise: be sure, when studying a show, that you are watching it in prime time rather than in syndication. Shows that go into syndication often have more commercial breaks added. If, for any reason, you aren’t clear on how many acts your particular show has, try (as I previously recommended) to get your hands on a sample script from the actual show. As you will soon see, in television scripts, Act Breaks are physically written in, so it will be extremely easy for you to figure out whether your show is following two-act structure or three-act structure.

Of course, there are exceptions to every rule. Series that are produced for pay cable networks such as HBO and Showtime and for streaming services like Netflix do not have Act Breaks. These shows go all the way through from beginning to end without interruption. If you are writing or pitching one of these shows, you don’t have to worry about creating strong Act Breaks. But other than that, the stories are still basically structured the same way and include all of the same elements as other comedies.

One last thing to pay close attention to is that some shows have cold openings and tags. These small segments that appear at the beginning and at the end of a script are generally much shorter than Act Breaks. A few words of caution: when trying to determine how many acts a show has, don’t confuse cold openings and tags with Act Breaks. They are not one and the same.


A cold opening, also known as a “teaser,” is the first few minutes of a show before the main credits. Its main purpose is to tease the audience and get them immediately hooked on the show, thus beating out the competition right from the get-go. At the top of every hour and/or half hour, much of the audience has clicker in hand, flipping around to see what’s coming on. Which do you think viewers would find more interesting: the main credits of a show or a small, hilarious snippet of the show? Of course, most people would prefer the latter. Networks bank on that.

Cold openings vary from show to show. In some shows, the cold opening has nothing at all to do with the main story of the episode. It is completely separate. In other shows, the cold opening actually helps set up the main story. Most shows are consistent: they either do a cold opening each week or they don’t. Occasionally, you might find a show that varies from week to week, but this is rare.

Should you include a cold opening in your spec script? The answer is, it depends on the show. Remember, you are trying to make your episode look exactly like the show you are writing. Therefore, it is imperative to do exactly as they do. If they have a cold opening every week, then you should definitely write a cold opening. If the show you are writing for does not have a cold opening, then putting one in would look like you don’t know the structure of the show. In those infrequent cases where it could go either way — as in sometimes they do, sometimes they don’t — I would definitely recommend doing a cold opening. It’s another opportunity to get a chunk of funny into your script.


A tag is a little two to three minute segment that comes at the very end of a show right before the closing credits. In fact, sometimes the end credits roll over the tag. In some ways, you can think of a tag as the opposite of a cold opening. The thing that makes tags and cold openings different is that while a cold opening can set up a story and in essence be part of the first act; a tag should never resolve the story. It should not be seen as part of the last act. Rather, it should be a separate block that stands completely on its own. You should never end your “A” story — or any story for that matter — in a tag. All stories must be wrapped up by the last scene in the final act. The reason this is important is that when a show goes into syndication, it often gets edited a tad differently in order to add in more commercial breaks so that local TV stations can increase revenue. In this case, the tag may not be shown. Likewise, the tag may not always be shown in foreign markets. Therefore, if you were to resolve a story in the tag, and the tag gets cut, a large chunk of the audience would have no idea how the story ended.

Tags can be small extensions of the story — some little funny add-on that happens after the story resolves itself. Or they can be as simple as using some outtakes of the show.

Should you include a tag in your spec? Like cold openings, the answer is, only if the show you are writing regularly uses a tag. If it does, definitely write one.

Excerpt from Write to TV: Out of Your Head and onto the Screen, 2nd Edition by Martie Cook © 2014 Taylor and Francis Group. All Rights Reserved.

Image by Chris Halderman via Flickr

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