When Kate meets Nathan, he reveals the existence of the Guardians--men and women with God-given "superpowers." But not all Guardians honor their calling to protect innocent lives. Some choose to prey on the innocent instead. Nathan's touch leaves Kate with a flame-shaped mark on her wrist, the sign she's been chosen as a Guardian. Suddenly she finds herself in the middle of a conflict that's been burning between the Guardians and their Fallen...