The two that are one must become the one that is all. One to save the world, one to destroy it. Sophie and Josh Newman traveled ten thousand years into the past following Dr. John Dee and Virginia Dare to the home of the Elders at Danu Talis. But this is no ordinary island--it is the legendary city of Atlantis, and Scathach, Prometheus, Palamedes, Shakespeare, Saint-Germain, and Joan of Arc are also there. Here, as the Flamels take their final breaths, the battle for the world begins and ends. Except no one is sure what--or who--the twins will be fighting for.