Maybe 3.5, but I'll round up to 4 because writing 12 books in a series that has done as well as this one (overall) is a huge deal and I think deserves respect. That's a lot of strings to tie together at the end. I felt that this book was much more in line with the early books in the series than the ones in the middle. Honestly, I didn't even read books 10 and 11...I had gotten too fed up with the books 7-9 and book 9 sort of did me in. So I decided to just cut my losses. Then I saw this book last week and realized this was the final book in the series. I couldn't resist. I went to Wikipedia to catch up on main events in books 10 and 11 and then read this one. I'm glad I did. It was a nice ending to a long story and while I am sure I would have gotten more out of this book if I had read the previous two books, I understood enough from all the other books I had read plus the wiki that I could follow it just fine. Zoey isn't making as many mistakes and I like a book about redemption. So, for a final book, I think it wrapped up the series nicely and reached back to the mood and tone from book 1, which I was glad to see.