The Enchantress by Michael Scott

Nicholas Flamel appeared in J.K. Rowling's Harry Potter—but did you know he really lived? And his secrets aren't safe!Discover the truth in book six of Michael Scott's New York Times bestselling series the Secrets of the Immortal Nicholas Flamel.

The Location: The home of the Elders.
The Time: The last day of Nicholas and Perenelle Flamel's long existence.
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.
"The Secrets of the Immortal Nicholas Flamel has everything you loved about Harry Potter, including magic, mystery, and a constant battle of good versus evil."— Bustle
Read the whole series!
The Alchemyst
The Magician
The Sorceress
The Necromancer
The Warlock
The Enchantress