Warning: Contains spoilers from Sanctus (Book 1) and The Key (Book 2).
Like Sanctus this book was fast paced. It starts with Liv in the hospital after she has escaped with Gabriel and Kathryn’s help from the Citadel. While in the Citadel Liv is fatally wounded but is saved by the healing power of the sacrament however, the sacrament is destroyed and it’s power has been transferred to Liv. She eventually checks out of the hospital on her own.
While in the hospital, Kathryn reads a book with a secret note from her father telling her about a second prophecy. This will become the guide to what Liv must do to save the world. Unfortunately she is killed by an assassin sent by the Vatican to help “clean up” the Citadel’s mess. Gabriel arrives at the hospital a little too late to save his mother. Then goes in search of Liv.
Several priests are also in the hospital and each end up dying from this new plague that causes them to scratch their skin bloody. Inside the Citadel many other priest are suffering from the same mysterious plague. The monks are being held in various states of quarantine. I found this a bit sad considering that most did not know what the sacrament was or how awful a secret it was to keep. However, there are still monks that knew and deserved the punishment.
Gabriel continues to help Liv to escape the Church’s assassin sent to kill her. They eventually end up in the Syrian desert where they must complete the second prophecy. They receive help from the mysterious man going by the name of “The Ghost”. They eventually figure out where Liv must be to fulfill the second prophecy and make it there just in the nick of time. However, along the way Gabriel discovers the truth about his father’s death and then loses almost everything. He turns out to be infected with the same illness that plagues the monks of the citadel. Now Liv must figure out how to save him from the plague with no obvious cure.