Sister Josepha Montafiore investigates phenomenon that may indicate the Biblical end of days. Astrophysicist Dr. Richard Massey is living through the aftermath of his daughter's murder at the hands of Satanist Isaiah Haden. When a young girl is struck down by lightning, declared braindead and starts spouting Scripture in Latin, their worlds overlap and though he doubts, Massey starts to find reason to believe Sister Josepha.
Massey finds himself drawn into the search for the sole survivor of the Grecian shipwreck after he and Sister Josepha transport the comatose girl to sanctuary. Haden starts to gather followers in the prison. Massey and Sister Josepha worry that the Miracle Child is in fact the anti-Christ.
Massey and Sister Josepha find the supposed miracle child's mother and go to the Vatican seeking answers. Hawk falls captive of the Satanists after falling prey to temptation. Isaiah Haden tries to find the comatose girl.
Hawk is given a terrible option by the Satanic followers of Isaiah Haden who took him hostage. Haden continues to increase his flock within the walls of his confinement. Massey tracks down former followers of Haden for information that will help him find Hawk. Sister Josepha seeks out a Satanism expert. Rubio, Massey's assistant, is approached by the Sisters of Mercy for aid because they believe the convent is no longer safe from Haden.
Massey and Sister Josepha track down a Satanist expert who leads them into a hidden library. Once inside, they find a puzzle that will supposedly reveal the nature of the Anti-Christ's birth. Haden's followers attack the convent where comatose Olivia is being kept. Rubio is wounded during the attack. Olivia dies. Haden tries to break free from his captors with a prison riot even as Hawk is brainwashed by his.
The secret book yielded by the solved puzzle box sends Massey and Sister Josepha to Tiberias on the trail of the birth of the Anti-Christ and Hawk. Ogden brings Hawk to Haden. Massey and Sister Josepha warn the Vatican that the peace talks are in danger. Haden and Massey's conflict comes to a head.