This is young adult fiction, male protagonist. I like YA fiction, and I like when the author leaves things open-ended for interpretation by the reader; so I was ok with not knowing what happened to Anna, and all the loose ends that this story leaves—like why didn't Anna like Mr.Devon, or what was up with Anna's parents; (and all the parents in this book for that matter), and the elaborate setting-up of a code and map that ultimately meant nothing. I was not satisfied at the end for a different reason. The gloomy atmosphere that this story held was depressing, for one. This story builds on the theme of disappearing, using literal examples and symbolic ones, like the detached parents. It was creepy to me how all of the parents in this book were emotionally distant and mysterious to their kids.