How to Write a Trilogy: Balancing Story and Character Arcs Across Three Books

Writing a trilogy, whether it's fantasy, sci-fi, or one of the many of sub-genres is an exciting and rewarding challenge. As with any story, you get to build a world, create characters, develop cool magic systems, and tear your readers' hearts into pieces, but with the long form of a trilogy these things can really evolve.

After writing the Sisters of Jade Trilogy, I wanted to take some time and share my thoughts and research. With this post, I'll guide you through balancing story and character arcs across a trilogy, helping you avoid common pitfalls and keep readers hooked from the first page to the last.

planning of a trilogy takes time, with some important arcs between each

Trilogy vs Series

There are trilogies. And there are series. An series differs from a trilogy in more than just numbers. A series can follow your characters through their adventures, with a different problem or villain each time. Sure, you can utilize that same tone and flavour throughout your books, but you don't need that grand, three-arc structure.

Writing a series is a different beast, to be sure. Some writers create five, six, or even fourteen volume arcs with one long overreaching plot. The Wheel of Time is not a trilogy. Neither is the Malazan Book of the Fallen. But all the books still connect in one long, continuous story. Other series don't have the same connective arcs, but the individual stories are all in the same world. Discworld and The Saga of Recluse come to mind. Joe Abercrombie has his First Law Trilogy, and his Age of Madness Trilogy, but in between there are three standalone books set in that world.

Both ways are viable. Both can be great. But how you craft them is slightly different.

Understanding the Basics of Trilogy Arcs

Merriam-Webster Dictionary defines a trilogy as "a series of three dramas or literary works or sometimes three musical compositions that are closely related and develop a single theme".

Even though a fantasy/sci-fi/spec fic trilogy needs a big connecting narrative, each book should also stand on its own. Each story needs its own complete arc, while also connecting to the others to form a large, satisfying narrative. This also applies to character growth through all three books, making sure readers feel the payoff when they reach the end.

When you write a trilogy, think of it as three linked stories rather than one long book split into parts. Each book should have a clear beginning, middle, and end. This means all three have their own story arc—a problem introduced, rising tension, a climax, and a resolution. But beyond that, you also need arcs that connect:

• Book 1 to Book 2 to Book 3: The main arc that spans the entire trilogy, often involving the main conflict or theme.

• Book 1 to Book 2: In addition to their respective arcs AND the big main arc, the end of Book 2 should resolve or evolve something that began in Book 1.

• Book 2 to Book 3: Like the arc that happens over Books 1 and 2, something introduced in Book 2 should connect and continued into Book 3.

This might sound more complex than you want, but I promise thinking about these things will only help your writing.

If you really get into it, I feel there is a secret, 4th point here, that lies solely between Book 1 and Book 3, something that is introduced in Book 1, left aside in Book 2, and then completed in Book 3. This can tighten up the story, giving call backs to the beginning, and really layering a more complex and interesting story.

This approach keeps readers engaged. They get closure in each book but also feel the pull to continue because of unanswered questions or ongoing challenges.

Crafting Each Book’s Story Arc

Start by treating each book as its own story. For example, in Book 1, you might introduce your protagonist(s), antagonist(s), their world(s), and a conflict that feels urgent and complete by the end. Maybe they defeat a local villain or solve a mystery, but you should also lay some groundwork for a bigger threat.

Book 2 should raise the stakes. Your protagonist faces new challenges, perhaps allies become enemies, or the world changes in unexpected ways. This book often explores consequences from Book 1 and sets up the final showdown.

Book 3 delivers the climax of the trilogy’s overarching conflict. It resolves the main questions and character journeys, giving readers a satisfying conclusion.

Good grief, that sounds sooooooo dry... but I really think this is true. Each part needs to have some sort of satisfying conclusion. Even if you want Book 1 or 2 to end on a cliffhanger, you need a climax that gives the reader a sense that there was meaning and purpose to the story. Some sort of destination has been reached, even if it's immediately clear that more needs to be done before your protagonists can truly rest.

Weaving Character Arcs Through the Trilogy

Speaking of protagonists, don't forget they should grow and change across the trilogy too. The first book lays the foundation: who they are, what they want, and their flaws. You want readers to connect with them early on.

In Book 2, characters face challenges that test their beliefs and force them to evolve. Maybe a trusted friend betrays them, an enemy befriends them, or they must make a difficult choice that changes their path.

By Book 3, characters should reach a point of transformation. Their decisions and growth should feel earned, not sudden. This payoff is crucial for emotional impact, keeping the story more than just big space explosions and dark lords being defeated by magic swords.

Balancing Story and Character Arcs

The best trilogies balance plot and character growth, utilizing both to really hit the readers hard. The story drives the characters to change, and the characters’ choices influence the story’s direction. For example, a character’s alcoholism might cause a setback in Book 2, and then their rediscover confidence might turn the tide in Book 3.

Intentionally Unfinished Plot Threads

Alright, alright, one thing I hear often is that all the plot threads have to be wrapped up by the end. As with any rules about writing (yes, even these things I'm talking about in this post), take them all with a grain of salt.

While you want your main arcs to come to a satisfying conclusion, I find leaving some questions unanswered can be a powerful tool. Leaving some elements purposefully unfinished can inform the readers to the larger, continuing world you've created. But be careful not to overdo it. Too many open threads can frustrate readers and make your grand ending feel incomplete. Plan carefully which secondary threads will remain and which will be resolved by the end.

Practical Tips for Writing Your Trilogy

• Outline the trilogy early: Know your main story beats and character arcs before you start writing. This helps avoid plot holes and inconsistent character growth.

• Keep track of details: Fantasy and sci-fi worlds often have complex rules, histories, and characters. Use notes or software to stay organized.

• Balance closure and suspense: Give readers enough resolution to feel satisfied but leave enough mystery to keep them turning pages.

• Develop your characters deeply: Readers invest in characters more than plot twists. Show their fears, hopes, and changes clearly. Keep their actions in line with their personalities.

• Use recurring themes: Themes like sacrifice, power, or identity can tie the trilogy together and give it depth. Like plot points, use and expand on your themes (if you consider that sort of thing while writing) as your trilogy unfolds.

• Be flexible: Sometimes your story or characters evolve differently than planned. Adjust your arcs while keeping the overall trilogy in mind. I like to plan out major plot points, leaving room for change between them.

  
  

make an outline for your trilogy, but be ready to change it

My Own Experience Writing a Trilogy

When I wrote the 1st draft of Sisters of Jade, I didn't know it was going to be a trilogy. Only once I was done did I realize these characters had much more to do. It was then that I started crafting the larger narrative.

So, I took what I had and reworked it. (I needed to anyway, it was only the 1st draft.) I made a larger plan for the trilogy, taking what I had and enhancing the story. With a rough outline in hand, I started writing Book 2 and editing Book 1.

Once I had Book 1 (mostly) ready, and Book 2 in a good spot, I began writing Book 3.

It was important for me to know that things I had started in Sisters of Jade would pay off in The Gorgon Court. Once I had a real outline for Book 3, I knew which things I put in place in Book 1 would work or not. Some characters and arcs were cut completely. Other things needed to be added for a proper sense of foreshadowing.

For me, this format worked.

Final Thoughts on Writing a Fantasy Trilogy

Writing a trilogy is a rewarding way to tell a big story. By carefully planning story and character arcs, you create a rich experience that keeps readers engaged across all three books. Remember to give each book its own satisfying story while weaving in threads that connect the trilogy as a whole.

Your trilogy should feel like a journey for both your characters and your readers. When done well, the payoff at the end will make all the effort worthwhile.

I hope some of this helps with your own journey in writing a trilogy, and thanks for reading!