Perhaps you're thinking of a different title, or maybe you're combining two different series in your mind. If you could tell me more about the series you're thinking of, I might be able to help you figure out the next book.
For example:
* What are some of the books in the series you're thinking of?
* Who are the authors of the books?
* What is the general theme of the series?
Once you give me more details, I can try my best to help you find the next book in the series.