An intriguing main character is necessary for the success of any book, but even more important for a long book series. Your character should not be constant; instead, it should be enduring. They should remain true to themselves, so the character remains familiar even if a reader picks up book 3 or book 19.

The storyline

This is the most complex part of writing a long book series.

How do you keep things fresh while repeating/reusing the same themes?

In the case of J.D. Robb’s In Death series, the situation seems a little more severe. 

There is a murder (or murders). Eve is called to investigate. She goes through the motions, gathering and analyzing evidence, narrowing down potential suspects, until she gets the guy. 

That’s it.

So, how do you transform this “simple” premise into over 50 books while keeping each one unique and appealing?

Tweak one thing.

Make the victim different. 

Make the crime unusual.

Make the suspects unexpected.

Make the stake higher.

Hamper the investigation.

Make the main character struggle.

Change the location/setting.

Make the investigation personal.

Basically, take the formula of the story and tweak something. Make one or two changes such that the entire story remains familiar but the circumstances become unique.

This is what Nora Roberts does expertly, allowing her to maintain a steady readership for over 3 decades of writing.

In “Visions in Death,” Eve gets unwillingly involved with a psychic, who provides shockingly accurate visions of the circumstances surrounding the murder Eve is investigating.

Eve, a logical person, appreciates and utilizes the information but remains staunchly skeptical about the so-called psychic, and her skepticism becomes richly rewarded when further investigation links the medium to one of the crimes.

Twists like this keep the book series enticing even after so many books, allowing it to remain familiar: still a murder investigation series, but a new mystery every book.

The supporting characters/the setting

The reason why I group these is that they serve a similar purpose in a long series.

The police station, the mansion where she lives with her husband, her colleagues, her resolute police commander, her peppy partner; each of these characters/places is like a landmark in the readers’ mind, reminding readers of certain plot points and development.

Eve’s perpetual cold war with her butler; her appreciation/bewilderment with her enthusiastic partner; her love and admiration for her husband; her quiet respect for her commander; her reluctant yet tender relationship with her therapist.

These interactions, anytime they recur in a series, preserve familiarity and can also be transformed into variables to help give each installment a new look. They offer the author a channel through which the author can thread in a new plot line.

Conclusion

Once the decision has been made to write a long book series, the priority of any author should be maintaining the identity of the story while ensuring to evolve characters and plot lines. 

The characters, the plot, and the setting are the variables through which authors can control the narrative.

How to write consistent characters

Regularly revisit character profiles and refer to them as a guide. Ensure that character decisions, actions, and dialogue remain in harmony with their established traits and development. Consistency is not stagnancy; characters can evolve, but these changes should be justified and presented coherently.

I have a strange example regarding character consistency. J.R Ward has written over 20 books in the Black Dagger Brotherhood series, spanning decades and narrating the stories of numerous characters.

The character in question is Qhuinn, one of the protagonists in the book series. In book 15, one of the later books in the series, Qhuinn and the mother of his child get into an argument. This is a little complex so bear with me.

Qhuinn is a gay vampire warrior and is in love with his best friend, Blay. Before they get together (and as part of the chain of events that leads to them getting together), Qhuinn gets a woman, Layla, pregnant. A lot of things happen but now, in book 15, Layla has delivered the twins. Qhuinn and his now-partner Blay are settling into their roles as fathers.

Here’s where things get hairy. 

Layla falls in love. With a vampire who is at odds with Qhuinn and his Brotherhood. A vampire who has tried to kill Qhuinn in the past. A vampire who everyone knows to be very deadly. In fact, when she confesses to meeting him while still pregnant, Qhuinn is horrified, likening the experience to “using a cobra as a scarf.”

Qhuinn continues lashing out at Layla, one scathing insult after another. In another scene, the argument escalates and Qhuinn fires a gun in the same room where his kids are. He even refuses to look at the twin girl because she resembles her mother, denying her attention and care.

This book is quite polarizing in the J.R. Ward fandom. A lot of readers, understandably, were perplexed at Qhuinn’s behaviour. Qhuinn had always been a brash person and very likely to rush into a situation without thinking. But after getting together with Blay and the delivery of the kids, we saw him become a more well-rounded individual, focused on protecting his blossoming family and friends.

So the question on readers’ minds was: Who is this Qhuinn?

This is not a question you want people to ask as they read your book. 

Sudden, unexplained shifts in a character’s personality will undermine your narrative and alienate your readers. I don’t want to go into further detail about the plot and how this issue was resolved as the lesson is clear: create consistent characters. 

Yes, reading is subjective, up to the judgement of the reader. Some readers might disagree with your character, while others might understand and support their actions. However, it is your responsibility to ensure that your characters display consistent behaviours that can be backed up by previous actions or explained by their character arc.

What not to do when writing characters

Inconsistent behaviour will confuse and frustrate readers. If there are sudden, unexplained shifts in a character's personality, this can undermine the narrative's credibility.

Summary

1. Understand the need to create great characters

2. Detail the components of a character profile

3. Study descriptive writing techniques to bring your characters to life

4. Use symbolism in the physical appearance of your character

5. Understand personality archetypes

6. Create balanced, authentic characters

7. Make sure your characters have backstories

8. Define character relationships

9. Understand the motivations and goals of your characters

10. Write a great character arc.

11. Create realistic dialogue

12. Develop a unique character voice

How to develop a unique voice for your character

Just like good dialogue, establishing a unique voice involves understanding the character's background, personality, and worldview. Consider their upbringing, education, and any defining experiences shaping how they perceive and articulate thoughts. 

But a character’s voice goes beyond dialogue. Character voice involves sentence structure, vocabulary, tone, speed and topic.

Interactions between Harry Potter and his best friends, Ron Weasley and Hermione Granger, provide one of the best examples of character voice.

As the most intellectual in the group, Granger finds herself explaining her thoughts and actions to the boys, leading to a character voice that is expository and logical, but also overbearing.

Being the only member of the trio who grew up in the magical world, Ron tends to have a more balanced view of Hogwarts and their experiences at the school. Combined with the fact that he comes from a large family (unlike Harry and Hermione who are only children), Ron has a sarcastic, humourous but supportive character voice, well aware of the fact that his two companions come from a non-magical background. 

Harry Potter, our main character has a questioning character voice, mainly because the truth of the magical world was so harshly revealed to him. The existence of Hogwarts, the death of his parents and his status as a celebrity were a few of the things Harry discovered in a very short period. And so, Harry tried to question and reason with people and things, seeking to understand the world he was thrust into.

What not to do with character voices

As expected, the biggest pitfall to avoid is an inconsistent voice. Characters should maintain a consistent manner of expression unless a deliberate shift occurs due to significant plot events or character development.

If a character is known for using a certain tone of voice or specific expressions, abrupt change can blindside the reader. Think of iconic characters and their catchphrases. Hercule Poirot’s “these little grey cells”, Sherlock Holmes’ “the game is afoot”, and James Bond’s “the name’s Bond. James Bond.”

Such catchphrases form part of a character’s voice. Along with your characters’ accents, common expressions, exclamations, catchphrases and vocabulary, these should be noted and detailed in a character profile.

Summary

Maintain a character's unique voice throughout the narrative. If a character’s voice does change, ensure such change is with sufficient reason, such as character development or due to the plotline. Otherwise, fluctuations in character voice can disrupt the immersive experience and confuse readers.

Despite any confusion, authentic dialogue is essential to a story. It involves crafting conversations that feel natural and true to each character's personality. Dialogue is a powerful tool for revealing character traits and advancing the plot.

How to write authentic character dialogue

To create authentic dialogue, immerse yourself in the character's mindset. Consider their background, personality, and current emotional state. Pay attention to speech patterns, vocabulary, and unique quirks that distinguish their voice. Dialogue should serve a dual purpose: conveying information and revealing character nuances.

Dialogue must also be suited to the setting of the story.

An example of this is C.J. Sansom’s Shardlake book series. The story is set in 16th-century England and takes place during the reign of King Henry VIII. Matthew Shardlake, our protagonist, is a lawyer with a disability that sees his back bent at an angle. He often gets drawn into murder investigations and the plot follows the resolution of these cases.

As expected, the dialogue in Sansom’s Shardlake reflects the story's time. “Doublet,” “codpiece,” “dowry,” and “vainglory” are a few of the words used in the book series that you won’t find in more contemporary novels. Exclamations such as “Jesu,” “God’s wounds,” and “Pox on you!” are quite common. It is also not uncommon to find that words have slightly different meanings and are spelt differently.

Matthew Shardlake's words reflect his education and his profession. As a lawyer, we read Shardlake talking about contracts, legal proceedings, land agreements and inheritances.

The discrimination towards Shardlake’s disability is also displayed via dialogue. By the harsh words and gestures used by people to describe the lawyer, we see the bias people of that time had towards disabled individuals. Throughout the book, we see Shardlake called a “hunchback,” “crookback,” “bent back,” “humpback,” and a “bent spider.”

Painful and inflammatory as the statements are, they are a true reflection of the mindset of individuals at that time. This is what good dialogue should do. Convey information, reflect character nuances and be suited to the setting of the story.

Developing your characters effectively ensures that they evolve, learn, and change in meaningful ways. 

Forgive my handwriting.

How to write a good character arc

Study your plotline. Study your character profile. Study the inciting incident, the plot points, the climax and the resolution. How does your character react to obstacles as they arise? Are there significant changes in how your character reacts?

Plan character arcs that involve a natural progression from an initial state to a changed or evolved state by the end of the narrative. If your character is hot-headed and quick to action, how do they react at the end of the story? Are they calmer, and more likely to think before they act?

Consider the challenges and conflicts that will prompt this growth, as well as the lessons or realisations characters will experience.

Maybe brash action from your protagonist resulted in injury or the loss of a loved one. Consider how this affects your protagonist and how the change is reflected in their attitudes.

One prominent example is Lockwood in the Lockwood & Co. series by Jonathan Stroud. At the beginning of the story, we meet Anthony Lockwood, a young man with a lot to prove. After the suspicious death of his parents, Lockwood inherits their house and uses the space to set up the ramshackle ghost-hunting agency, Lockwood & Co.

Lockwood is…audacious, to say the least. Along with two other ghost-hunters, teenagers like himself, he tackles cases no one (in their right mind) will take on. Initially, we meet a charismatic but reckless young man. One with deep-seated trauma surrounding the death of his parents and his sister. He wants to prove himself. To his dead sister, to his parents, to the elite ghost-hunting agencies, to DEPRAC (the police-like agency-monitoring system), to Lucy and George (his companions). And most of all, to himself.

He is often brazen and impudent. But as his actions bring his colleagues and friends closer and closer to danger, we see Lockwood change. Anthony mellows. He thinks before he dives. He opens up about his past. He stops responding to provocative words. Yes, once in a while, we still see a glimpse of that cocky teenager, but at the end of each book (and the entire book series), we see a new Lockwood.

One polished by a great character arc.

If it isn’t obvious, I enjoyed Jonathan Stroud’s book series and I have read it numerous times. And each time, I see a new way to improve my character arcs.

This is what a character arc should do. Show growth and development.

What not to do when developing a character

Unrealistic and rushed character development.

This is a common pitfall. Characters must change in response to experiences (the plot), and these changes should be portrayed gradually and realistically.

Lockwood didn’t change in one chapter. He didn’t completely change in one book. His character arc spanned the entirety of the five-book series and it was a delight to read.

Summary

Foreshadow character development, showing the gradual impact of experiences on the character's beliefs and behaviours.

Do not rush character development or force changes that are inconsistent with the character's established traits and experiences.