Her world is suddenly upturned when Maanik, the daughter of India’s ambassador to the United Nations, starts speaking in tongues and having violent visions. Caitlin is sure that her fits have something to do with the recent assassination attempt on her father—a shooting that has escalated nuclear tensions between India and Pakistan to dangerous levels—but when teenagers around the world start having similar outbursts, Caitlin begins to think that there’s a more sinister force at work. In Haiti, a student claws at her throat, drowning on dry land. In Iran, a boy suddenly and inexplicably sets himself on fire. Animals, too, are acting irrationally, from rats in New York City to birds in South America to ordinary house pets. With Asia on the cusp of nuclear war, Caitlin must race across the globe to uncover the mystical links among these seemingly unrelated incidents in order to save her patient—and perhaps the world.

    Eight hundred years earlier, on the eve of a brutal crusade that will rip apart southern France, a young woman named Alais is given a ring and a mysterious book for safekeeping by her father. The book, he says, contains the secret of the true Grail, and the ring, inscribed with a labyrinth, will identify a guardian of the Grail. Now, as crusading armies gather outside the city walls of Carcassonne, it will take a tremendous sacrifice to keep the secret of the labyrinth safe.