Instruct: Classify a given review into positive or negative sentiment.
Query: Interesting scifi

The parallel storylines (half the story is told in flashback, alternating present-time and flashback chapters) allow Wilson to tease and pay off things well, and he's mastered the chapter ending cliffhanger. The first 400 pages of the book lead up to an amazing world-altering chapter. I found the concluding chapters to be a bit weak, unfortunately, with no real climax.