The first of seven brand new 39 Clues stories, leading up to one explosive reveal. Time is running out for Grace Cahill as she struggles to make the most important choice of her life: a decision that will shape the future of the Cahill family . . . and the world at large. After spending centuries lurking the shadows, the Cahills' enemy — the Vespers — are planning an attack, and sending Amy and Dan on a dangerous hunt for The 39 Clues might be the only way to stop them.