There is a little. I mean he keeps the thread going, but all three of the first books have a satisfying ending for the main story of the book. Future books would lose that. Actually my favorite book was the second. The ending of that one was epic, better than the first, and made us feel like the conclusion was short at hand. Too bad the third book immediately walks us back from what the ending of the second suggests. If you did want to get into the series, I'd suggest at least the first two, possibly the third if you are enjoying yourself. From that point you might be better to just read the Wikipedia summery.