Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Fantastic setup, weak second half

This is my first Mieville book and he had me for the first 300 or so pages. He did a fantastic job making me feel the horror of the city, its drippings and putrid air. The plots were creative and interesting....but these get abandoned for the second half of the book which is basically a monster chase against inter-dimensional moths. I felt like I was reading two books in one, neither of which satisfied the other. As the book wound down I found the reading to be exponentially tiresome, and I didnt bother to finish the last 70 or so pages. It is extremely rare for me to not finish a book.I give Mieville credit for his wicked imagination and for teaching me some new words. There were parts of the book that blew me away, but unfortunately few of these occurred in the last 400 pages.