I like writing characters that spans multiple stories. It’s the actual job of world building, with the understanding that each lore and history of the world is an individual story in itself.
In the 139 Trilogy, many characters cross from one book to another. Now, you might be saying that’s the reason for the ‘trilogy’. But the 139 Trilogy was written as standalone novels, though they have a larger storyline that very loosely connects all three.
Quite recently, I’ve started reintroducing characters into the last book of the trilogy, and I found quite an internal struggle while writing them.
Most of the characters coming back were major characters in the book of their first appearances. Being so, I had to resist the urge to write them as major characters in their comeback, when in fact, they were returning as minor and supporting characters.
This meant lesser dialogue and focus, or lesser chapter of appearances. This is something I felt key to keeping the story centred. You know who these characters are and what they can do, but you also know that they are not the key parts of the tale that’s currently being told.
I used a few ways to introduce recurring characters. One of them is as background. They make very, very minor appearance. Maybe as a street vendor, or just a shop owner that has a short interaction. Of course, I don’t do this simply to show an old character, but to demonstrate how the books are connected.
Another method is to have them return as a supporting cast in a suitable roll. A doctor or salesperson are the simplest fit. Just try them in the role of the time you need them to, with good reasons of course. I like doing this, and I’ve done them quite often, because when you’re writing these characters in these one-off chapter(s), they are already fully developed, meaning they read more realistically and full than a meandering background character plucked out from a barrel full of randomly named people.
Of course, there is the most popular method, because we all get caught up in writing, and that is to reintroduce these characters as main casts. This is hard, because it borders on fanfiction. You don’t write the story as itself, but write it to fit around this new character being introduced.
But it is possible to do this right, and I think the only real way is to plan to do it from the start. My recently finished Chronicles of Tearha: Keep Walking, has a character called Lucinda Baerrinska, and I brought her into The Number 139. This wasn’t something out of the blue. I had her full backstory of Keep Walking drawn out a long time ago, and I wanted her to be in The Number 139 since the conception. I started writing Keep Walking afterwards. This made her appearance in both story a natural fit.
So in a nutshell, the best ways to write a recurring character is to plan their appearances. Either minor, small, or major, just make sure they fit.