Fourteen-year-old Amy Cahill and her younger brother, Dan, have been traveling the globe on a highly dangerous hunt for the 39 Clues. Through all the betrayals and near-death experiences, one single belief has kept them going: they are the good guys. But when they arrive in China, a shocking discovery completely shatters their reality. They uncover a dark, deeply hidden secret about their parents that changes everything they thought they knew about their family's past. For the very first time since the hunt began, the intense pressure tears the siblings apart. They have a massive argument, and soon after, Dan completely disappears into a country of more than a billion people. Now, Amy is left entirely alone and facing an impossible, heartbreaking decision. You will follow her frantic journey through crowded streets and ancient temples as she weighs her options. Should she continue the desperate search for the next Clue to stay ahead of their ruthless relatives, or must she abandon the hunt entirely to track down her missing brother? The stakes have never been higher for the Cahill kids.