Mask and the Underworld

As winter approaches, four people are hospitalized in critical condition at different hospitals across the city. Only one thing seems to link them: an esoteric symbol drawn on their wrist.
While the Prosecutor's Office wants answers, the Vatican fears that something horrifying may be lurking behind the mystery.
Ettore Borgia is a criminologist working as an archivist in the Vatican. Thanks to his seemingly dull job, he has spent years unearthing secret documents, disturbing testimonies, and inquisitorial records-centuries of hidden knowledge from within the Catholic Church.
Known in legal circles as an expert in the occult, he is summoned to shed light on the darkest corners of human delusion.

"The Mask and the Underworld" is the first volume of the trilogy The Call of the Apostles.