Book 2 in the Secrets of the Immortal Nicholas Flamel Series
This is a "young adult" book, but it has so much depth it probably could be an adult book. I certainly loved it as much as the first book in the series, The Alchemyst. In this book Sophie's powers have been Awakened, but her twin brother, Josh's have not. Sophie has begun her training in elemental magic and Josh feels left out and jealous. Meanwhile the two, along with Nicholas Flamel and the Vampire Warrior are being pursued by other's serving Dark Masters out to harm them. A thrilling, exciting, escape into a world of immortals, magic, and Elders.