Innocent Blood. The Order of the Sanguines Series

In this riveting follow-up to The Blood Gospel, the first book in the thrilling and atmospheric Order of the Sanguine series, New York Times bestselling authors James Rollins and Rebecca Cantrell deliver a tale of international adventure, intrigue, suspense, and supernatural mystery involving a modern scientist, a highly secret eternal spiritual order, and a terrifying power who must join forces to bring down a ruthless and cunning enemy and prevent the Apocalypse.
While exploring a tomb hidden for centuries in the depths of Masada, Israel, brilliant archaeologist Erin Granger began an incredible journey to recover a miraculous ancient artifact tied to Christ himself. The quest introduced her to a diabolical enemy determined to discover the book and use its powers for his own dark ends. It also led her to an ancient and highly secret Vatican order-known simply as the Saguines.
Though she survived, the danger has only just begun .