This is the second book in the series 'The Order of the Sanguines', where the priests, and their allies, must fight the forces of darkness. This time, a man claiming to be Jesus' betrayer, Judas Iscariot, is determined to open the gates of Hell, using the First Angel.
I found the history, both religious, and past, to be very fascinating, and the fantasy well written. Once again, James Rollins at his best.