by Becca Puglisi
I’ve been thinking a lot recently about character chemistry—that spark, bond, or shared connection we often associate with strong and compelling romantic relationships.
But chemistry shouldn’t be limited to love interests. Frodo and Sam, Thelma and Louise, Luke Skywalker and Darth Vader…some of the most memorable relationships in fiction had nothing to do with physical attraction. If we can bring chemistry into the protagonist’s friendships, rivalries, or even mentor/protégé and adversarial relationships, the characters and dynamics will come alive for readers.
So I’d like to share six tips for creating that oomph between characters in any genre.
Tension—the reader’s emotional response to what’s happening with the character—is a key element of chemistry and can be generated through conflict, suspense, uncertainty, and anticipation. When we examine tension within the context of relationships, it often arises through the interplay between the characters.
Even positive and symbiotic relationships need tension to keep them moving. So give the characters opposing traits—impulsive vs. cautious, logical vs. intuitive, tolerant vs. inflexible—to create that sense of strain. Maybe they have conflicting goals, or they’re pursuing the same objective but for different reasons. Are they opposed when it comes to certain questions of morality or ethics? Differences create friction, and friction creates interest. So make sure your characters challenge each other simply by being true to themselves.
Everyone wants to be seen; it’s something we look for in our real-world relationships, so adding that element to a fictional dynamic can give it an extra dose of authenticity. Maybe one character sees something in the other that most people miss: an undervalued strength or how they’re uniquely different. Maybe the character sees a friend’s flaws and weaknesses and are able to call those out in a way that’s challenging rather than critical. This depth of knowing each other speaks to a deeper kind of relationship that most readers appreciate and will respond to.
I recently rewatched the TV show Lie to Me, and in the first episode, the protagonist claims that people on average lie three times per hour. I don’t know if that’s true, but it feels true. Whether we’re lying outright or covertly being deceptive (leaving out details, pretending to feel something we don’t, etc.), no one is completely honest all the time.
Authentic characters hide things: their true feelings or opinions, what they really want, their insecurities and fears—even from the people they love and trust. So a character’s surface-level interactions (their words, choices, and behaviors) contradict what’s really going on inside (visceral responses, thoughts, and emotions). That subtext charges the energy in the relationship, making it crackle.
This kind of chemistry is compelling to readers because it adds a sense of realism to the relationship. It also creates intrigue as the reader sees everything isn’t as it seems, and they start paying closer attention to figure out what’s happening under the surface.
Chemistry builds on shared experiences—good and bad. When you’re creating characters and their important relationships, add in backstory events that reveal a bond. When they reference those touchpoints, it reveals a depth to their relationship. If the characters are just getting to know each other and don’t yet have a history, create bonding moments—even something small, like a shared joke or win—to start building that depth early.
Chemistry is anything but boring, so it’s hard to find it between boring, predictable, or clichéd characters. What can you add to the relationship to make it unusual or interesting?
Relationships are only as engaging as the characters who embody them, so invest ample time and energy in the character creation process to be sure you’re building a unique and authentic cast that readers will find interesting.
Chemistry is very much about shifts and changes. A relationship where both parties are content and comfortable and everything stays the same will read as flat. One way to address this is to map out the relationship arc—all the characters’ interactions—throughout the story. Mark those events with a + or – sign to indicate strengthening (increased admiration, proven trust, bonding through adversity) or a decline (increased distance, an argument, loyalty being questioned). If you don’t see changes (if the relationship is mostly flat) add moments that create movement. This will keep it from stagnating, giving the relationship a sense of flow and evolution.
Basically, chemistry emerges not only from what the characters say and do, but through how they engage with each other. Big moments have big impact, but you can only have so many of those in a story. Capitalize on the small things that can bring about friction, camaraderie, subtext, and uncertainty in the relationship, and readers will be drawn in.
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Becca Puglisi is an international speaker, writing coach, and bestselling author of The Emotion Thesaurus and other resources for writers. Her books have sold over 1 million copies and are available in multiple languages, are sourced by US universities, and are used by novelists, screenwriters, editors, and psychologists around the world. She is passionate about learning and sharing her knowledge with others through her Writers Helping Writers blog and via One Stop For Writers—a powerhouse online resource for authors that's home to the Character Builder and Storyteller's Roadmap tools.
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Character 'chemistry' is a perfect descriptor!! Don't you love how atoms/characters collide, tugging and pulling, and pushing away? Breaking bonds, reforming bonds, creating new bonds, unexpected bonds. Crashing into molecules, forming unexpected or new elements. And don't get me started on catalysts. Yes, I say! Not 'bio' chemistry, but 'chara'chemsitry.
I love the reactions I get when I mix character chemistries in my stories!
All that to say - this was an eloquent course in chemistry!
Thanks for reading, Jennifer!
Without chemistry, our world would be one big bare rock. Instead it blooms with life. Same with our emotions. We'd be nothing without them and how they gently nudge or forcefully shove us in different directions. Great post, Becca! I love your clarity and wisdom!
Best of luck with your writing, Sarah!
I love this post, Becca. Whether I'm reading or writing, the small moments in a story absolutely make it work (or not) for me.
Thanks so much for hosting me, Lynette :).
Great summary on how authentic tension and conflict are layered in small moments and multiple ways between the characters, not just through the external plot. Thanks!
When I think of tension and conflict in real life, so much of it comes through relationships—the important and the superficial ones. So it makes sense to build this naturally into those interactions.
Great post, Becca! I Love all of these tips about creating great chemistry. I think every writer needs this reminder!
Thanks for reading, Jenn!
I love all of these, Becca, but I super-love #6 (Ebb and Flow) because of the practical task that let's you see if you're balancing the relationship arc. Really helpful!
I think it was Blake Snyder (Save the Cat) who suggested using index cards for each scene and mapping out the emotional change——making sure what the protagonist feels at the beginning of the scene isn't the same as what they feel at the end. I loved that idea for visually mapping the story; there are so many things you can track, and the relationship arc is one of them :).
I love that idea, Becca. And that Blake Snyder was a super nice guy. I was lucky to see him in person before he died. I'll try this tip too!
great tips
This is so helpful, Becca--and an area where I frequently see authors struggle: putting potent character dynamics on the page. I'm bookmarking this helpful post as a resource, and sharing it in my editorial newsletter for authors.
Excellent post on how to build character relationships that feel authentic. Thanks for sharing!
Of course! We all love to share. 🙂
I want to come back and read this many times, thanks!