Writing a Series - a Piece of Cake?

What is it about series that keep bringing people back? I adore series, and if given the choice between an author who writes stand-alone books and another who writes a series, I'll take the latter every day of the week.

Book two of The Carolina Slade Mystery Series sits in the hands of the publisher. Book three is in edit-mode. Book four's outline is started. And I'm learning what it takes to write a book series. It's way more than I imagined. While  my experiences might not be those of other series writers, I have stumbled and studied and learned a few lessons along the way:

1. The protagonist has to grow in each book.

As writers, we understand our protagonist has to evolve into a different person in some way by the end. A series does not change that. In book two, three, and so on, she still has become a better person because of the obstacles overcome. Imagine doing that for 22 books like Sue Grafton!

2. Back story must be sprinkled carefully.

A new reader may pick up book two and have never read book one. Since your protagonist is evolving, you'll find the need to fill in gaps. But they can't seem like you're filling in gaps. You have to sprinkle in back story with comments, asides, internal monologue, and reactions in carefully planted sentences. No chunks of history. No explanation of "last time." It must be slid in seamlessly, noiseless, without notice.

3. Bring forward the little things.

Don't forget the cat. I'm into book three right now, and I forgot to mention Madge the cat. Thanks to a keen eye of a critique member, I went back and included her. The new house established in book two needed description in book three. The difference between Wayne's job and Slade's job has to be reiterated. Usually one-liners work well in many instances, but sometimes the reader needs an education. But like back story, you cannot go into depth with it.

4. Never remind the reader there are previous books.

Each book has to be a stand alone. Yet each book still must weave into the next and carry remnants of the prior . . . without feeling like a trilogy. It's like layering a cake then frosting it. You know it has layers, but you don't really want to see them.

5. Keep the timeline straight.

How much time lapses between books? While it may not matter much for the adults in the books, a year can make a big difference in kids and their behaviors.

Series are fun. After all, many of the characters are already 3-D developed from the debut title. And everyone knows the readers love to "come home" to a series, already knowing the players. Just remember that the rules of the first book apply to them all. Each book has to feel as remarkable as the first. Being comfortable in a series doesn't mean you can take anything for granted. Stay on your toes.