Peter Tremaine (the pseudonym of the English writer Peter Ellis) is called the creator of the “Celtic thriller” - a series of novels about an insightful and courageous Irish nun, Sister Fidelma of Kildare, a girl of royal family and heiress of ancient Celtic wisdom. This time, Fidelma and her partner, the monk Eadulf, are conducting an investigation in Rome on behalf of the Pope himself: the Archbishop of Canterbury, who came for the papal blessing, turns out to be strangled in the bedchamber of the Lateran Palace, and the gifts of the Saxon kings he brought were stolen. Who did the ambitious archbishop cross? And what kind of strings connected him with the legendary Library of Alexandria?