How to create chemistry between your characters

You know that moment when you’re reading a book and you find yourself smiling as you read or crying, even? It’s that moment when you realise how fully invested you are in the characters and that’s what I always look for in a good book as a reader. It’s also what I hope to achieve as a writer.

Creating chemistry between any characters in a book is of the utmost importance to keep readers engaged, so, of course, creating romantic chemistry between my hero and heroine is my top priority when I plot my next book. It might seem obvious, but before I can even think about creating that chemistry, I first have to know who my hero and heroine are. I usually begin with one of them, depending on which one sparked the idea for the book. Their personality, their motivations, their past, their present and where they’re going.

Once I know those things, I can think about the kind of partner that will create chemistry with them on the page. While physical attraction is important, it requires the addition of emotional and intellectual chemistry because that’s what drives the story. Sometimes chemistry starts from an antagonistic place in enemies-to-lovers romances where the hero and heroine meet in conflict and their interactions are tense and filled with sharp-witted banter. There is a journey through misunderstandings and miscommunications that are overturned in delicious moments of honesty where the characters learn to see each other in a new, favourable light.

In my romantic comedy A Cosmic Kind of Love, however, the chemistry begins before the characters physically meet. Often, we’re attracted to personalities that are similar to ours but also to personalities that are our opposite.

That opposites-attract chemistry is what I leaned into for A Cosmic Kind of Love. Through video letters, the Hallie’s attraction to Chris, a NASA astronaut, begins with intellectual and emotional chemistry. Yes, she thinks he’s attractive, but she hasn’t met him, and his intelligence and charisma as he explains his day-to-day life on board the International Space Station with humour and modesty is what appeals to her.

For Chris, the attraction is emotional as Hallie sends him video letters where she bares her soul and is totally vulnerable in a way she isn’t with any other person in her life. He’s captivated by her kindness and also frustrated by the way people in her life seem to take advantage of her tendency to people-please. She’s warmer, more down-to-earth, than most people he knows and even himself to an extent. Hallie enjoys Chris’s confidence and life experiences because they’re so different from her own. He’s capable and self-assured in a way she isn’t and that’s attractive to her.

When the characters meet on the page, that’s where it was important to build on their physical chemistry. I avoid over-describing my character's appearance to portray their physical attraction to one another because I feel that’s more telling than showing.

There are subtle but impactful ways to create chemistry without physical descriptors by highlighting their awareness of one another. If I think about my own reactions to someone I’m attracted to – hyper awareness of that person is most notable. Therefore, I put that into my characters. How she gets goosebumps when his hand brushes hers or his heart races a little faster at her proximity. I note his heightened reaction to the way she laughs and the flutters in her stomach when he smiles, etc.

That physical chemistry only intensifies as the characters grow to know one another and their connection develops into emotional chemistry. A good way to build on it is to have your hero or heroine (or both) tell the other they love something about their physicality that they themselves don’t like. It’s often true that we can’t see ourselves how others do, and I enjoy portraying that notion in my novels.

For me, it’s also important that the hero and heroine share important conversations about past relationships, perhaps even past traumas, and that they confess feelings they haven’t shared with anyone else. This is not only a wonderful way to create three-dimensional characters, but to portray the level of trust that’s grown between them. That way, the reader should hopefully believe wholeheartedly in the special chemistry between these two characters. 

For me, as a writer and a reader, I need to feel both the physical and emotional chemistry between my romantic leads in order to fully buy into their connection. One without the other leaves the relationship feeling a little one-dimensional, so it's important as a writer to focus on both aspects of their attraction.

Samantha's top tips for creating chemistry:
•    Know your characters well before you start writing.
•    Break your plotting down into physical and emotional chemistry. Intellectual chemistry is also something to think about.
•    Physical chemistry: physical awareness to touch, proximity, scents. Physical attributes that are particularly appealing.
•    Physical chemistry: physical reactions to the above. Stomach flutters, heart rate, sexual reactions. Be careful not to overuse descriptive reactions because it can become distracting to the reader.
•    Emotional chemistry: decide if your characters are alike or opposite or a mixture of both. Conversations of shared experiences or experiences they haven’t spoken about to anyone else are a great way of creating a special bond and trust between the characters.

A Cosmic Kind of Love by Samantha Young is published by Piatkus

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