I don’t want to spoil the plot, as there are many twists lurking within this book, so I’ll just say this:
This is the best one yet.
Books 1 and 2 were occasionally intense, but mostly I liked them because they were hilarious. Book 3 was the one that really sucked me in, with its tightly woven, ever-twisting plot. Book 4 sprawled a bit too much but brought lots of romance and character development. Book 5, too, meandered far too much and lacked the comic relief that lightened earlier books,