Twelve-year-old Hazel Moore and her mother arrive at Los Alamos, New Mexico, to be reunited with her physicist father. It is 1944, and war is raging on five continents. Hazel doesn't know why her family has come to this mysterious, remote place. She doesn't know what her father is working on, night and day, in the secret laboratory. But she's determined to find out. Will she be able to uncover the mystery of Los Alamos? And how will the secrets of this place change her family forever?