This book breaks my heart and heals it all at once. It is so beautiful written, Nicola Yoon has created such an astounding story with rich characters. I thought the science and the history that was woven into the story was so perfect. I finished it in a day and I can't remember the last time a book had that much power over me. This book will make you laugh, make you cry, it will change the way you look at life and I hope it will make you believe even just a little bit that some things are "meant to be".