There’s nothing nicer than finishing a great book and then realizing that it’s part of a series. You know that you’ve got so many more books to read—yay! But what is it that’s holding that series together?

There are different types of series: those where there’s one story that lasts for many books, and those that are many different stories with one common element tying them together. In romance, series are usually the later since each book has to have a happily ever after to be considered a romance.

An example of a romance series is Bridgerton which readers of historical romance have loved for years and now the rest of the world has gotten in on the secret. It’s the story of one family with eight children. Each book is the story of one of the children as they find love and marry.

But think about the Harry Potter series. Clearly, it’s not a romance, but each book is a satisfying story in and of itself. At the higher level, the series as a whole also has a story that is carried over from book to book slowly developing throughout the series and culminating in the last book.

Can an author do that with a romance series as well?

If Julia Quinn, author of the Bridgerton series had, for example, introduced a character at some point—ideally, in the first book—to become the love-interest of Violet Bridgerton, the family’s mother it would have done the same thing as the Harry Potter books. There could be an over-arching romance that slowly grows from book to book and ends in the last book with its own happily ever after.

To me this seems like a very neat way to write a series.

I have written a number of series where all the books are tied together in some way: friends who show up in each others’ books (The Merry Men Quartet), a group of ladies who get together to play cards each of whom has her own story (The Ladies’ Wagering Whist Society), a woman destined to give birth to the most powerful witch in generations (The Storm Series), and so on. But each of these are individual books with a common theme or cast.

Currently, however, I have begun a new series—the Zodiac Series. As you would expect, it follows the signs of the zodiac with the heroine of each book being the next sign in order–there will, eventually, be twelve books. The books are tied together not only with the zodiac theme, but with a matchmaker who matches people based on their sign. Since she shows up in every book and is a central character, I saw no reason why she shouldn’t have her own romance, and what better way to do that than by introducing a character (the concept was introduced in the first book, but the character doesn’t actually show up until book 4) who will eventually become the matchmaker’s match (with the last book because her story).

But in order to write this, I have to step back and look at the bigger picture. I need to plot out the matchmaker’s story and how it intersects with each and every story in the series. That’s not easy for a twelve book series where I have been plotting each book individually as I get to it.

I’m currently about to start writing book #4 and have absolutely no idea who will be the main characters of book #5. All I know is that the heroine will be a Leo—the fifth sign of the zodiac. I suppose I could try to decide who all the main characters will be now, but it’s unlikely that I’d stick to it. Things tend to happen in books. Characters are created who then call out for a book of their own. (This is how I got the hero of the fourth book—he was a secondary character in book 3 who insisted on a story of his own.)

Still, no matter who the main characters are of each book, I will know exactly how the matchmaker’s story must progress in that in book. Once I’ve got her story worked out, I’ll need to split it up so that a small part of it plays out in each book—not as a major element, but just so that it’s there and once the reader gets to the last book, they can think back over the series and recognize the little hints I gave throughout the series which lead to the last book. Of course, this assumes that a reader will read all twelve books, but an author can hope, can’t she?

So, do you write series? Love to read them? What do you have tying the books in your series all together?