In the Armenian Cathedral of St. John the Baptist in Paris, Chilean refugee Wilhelm Getz—the choir regent for boys and an organist—is murdered. Kasdan, a retired police officer and a parishioner of the cathedral, immediately begins his own unofficial investigation. He is joined by Volokin from the department for the protection of the rights of minors. It turns out that in the past, several boys from the choirs Getz led disappeared. After the first crime come even more bloody murders. Between the full of danger investigation that the heroes get drawn into and the ancient choral “Miserere,” there is a mysterious connection…