How to Write an Addicting Novel Series

This is how I write series books, because I'm a reader first and I know what I like to keep me interested.

So firstly, be sure to have a bad guy or conundrum that runs through 3 books, solved at the end of the 3rd book. Make your series themed with underlying themes every 3 books. The entire series can be 9 books long, or even more! The hero solves a case in every book, but for 3 books there's also another plot-line haunting the MC.

The reason shows like Orphan Black and Extant don't work for m...