The Unknowns by Benedict Carey is a good book that gets you thinking. The writing gives you a good picture of the setting and the events. Each character has his or her own distinct attitude and characteristics. As the author's purpose was to use his degree in math and write a book including mathematics, I would say he exceeded his purpose. The book doesn't have a certain mood such as humor or sadness, but it is like your usual chapter book like Old Yeller or The Mouse and the Motorcycle. The Unknowns is overall a good book but its main weakness is it can be confusing at times. The confusion might depend on a readers age level because some of the math problems. Also, sometimes it hard to understand exactly what's going on because of some of the transitions. For instance, at a point in the book Di was separated from the group. It explained how she was separated, but not in a clear way. I thought this was probably because the book has not yet been edited. I would be surprised if The Unknowns becomes the next Harry Potter or Twilight series, yet I still think this book has great potential to become a bestseller. I would recommend it to young adults, who enjoy excitement and thrill.