Instruct: Classify Amazon reviews into positive or negative sentiment
Query: If you have NOTHING else to do, you can kill time with this book.

As a rave reader of mystery books, I was expecting a lot from this one. The summary and the reviews of this book were really appealing, and I really expected something at the DaVinci Code's level. NOTHING to do with it. Although it also deals with secret codes, the book is written very poorly. You always have the feeling of reading a book written by and for high school or university students, (like those who write to participate in contests) but you never feel like you have real literature in your hands. Even in the most important parts of the book, the authors never take you to the real climax of the story. I give it two stars because I think the plot is good, yet a lot more could have been done to make this book really worth to buy it and not get really dissapointed about it!