As usual, Sarah Rees Brennan delivers a fast-paced book brimming over with emotion, wit, and beauty. Unlike the first two in the trilogy, I had the general shape of the ending about 2/3 through, just not the details. That's not in anyway a problem with Rees Brennan's writing; in fact I count this as a positive. Generally when I read a book, I can predict how it will end and even most of the plot points about half way through. This doesn't take away my enjoyment of reading at all, but it does mean I don't often have the wide-eyed, story-lost wonder I had when I read as a child. Rees Brennan is a masterful writer, with an ability to draw the reader into her world and see and experience it all. Furthermore, she has these wonderful, clever bits of humor; one-liners that make me laugh out loud and ache with her characters. The first two books in this trilogy had me on the edge of my seat the entire way through; by this book I was familiar enough with her writing style and the character's motivations that I had figured out the general shape of the story and was just curious to see how she would unfold the circumstances to reach that conclusion. Given how surprised I was by the last two endings, I also wasn't 100% if I had figured out the endgame correctly, which is also a major plus for her writing.With this series, Rees Brennan did something unusual -- she switched the protagonist with each book. The first is from Nick's p.o.v., the second from Mae's, and the third from Sin's. I admit, Sin isn't my favorite character. Nothing against her; she's cool and clever and intriguing. But I really wanted to take Jamie's journey, and it was hard for me to be as invested in the book because I wasn't very interested in Sin's journey at all. However, the fact that Rees Brennan switched protagonist made certain parts of the book incredibly poignant and disorienting at the same time -- moments when Sin overheard or witnessed conversations and interactions between Mae, Jamie, Nick, Alan, and Seb. It was incredible and fascinating and heart-wrenching to see these interactions in flashes and bits, and I often felt this frustrating sense of loss, as though there were all these parallel stories and plotlines going on that I was just getting the barest hint of, not the experience of. It was actually incredibly done, and you have to admire the artistry of it.So, yeah, I didn't personally enjoy having Sin as the protagonist. I didn't dislike it, but I would have much preferred another character, like Jamie or even Alan. That said, I think Rees Brennan did a great job with her choice, and I highly recommend the entire series. It's a great read.