The main character is supposed to be a gifted kid, but he doesn't apply this intelligence to anything other than maths and music. The amount of trouble he gets in without thinking of leaving anyone a note explaining where he's going to go is ridiculous. He has an idea at the end, which then solves a big part of the plot, but I was surprised that it actually worked. Clearly, the people he tricked have the memory of a fish because he wouldn't have been successful otherwise. His friends, also gifted, aren't any better. As a side note, I can't believe that none of them figured out the riddle.
The plot was very uncomplicated and everything is obvious from the beginning. After reading the synopsis, I was expecting more action or at least more mystery. I know it's YA, but the synopsis suggests that it is a thriller and it has a sniper on the cover. My main issue with the plot is that it disappointed me a lot, but I probably would have considered it ok if I had had different expectations. This is why I gave it 2,5 stars instead of just two.