Black Book of Hours

2022, Vitoria, Basque Country. Former police inspector and profiler Unai Lopez de Ayala, better known as Kraken, received an anonymous call. The caller informed him that he had one week to find the legendary book "The Black Book of Hours of Constancia of Navarre," a priceless bibliographic gem. Otherwise, Kraken's mother, who is in the hands of a criminal, will die. Unai is in shock. His mother, Martha Gomez, has been resting in the local cemetery for 40 years. But the DNA analysis of the blood from the kidnapped, obtained during the investigation, yields a shocking result: it really is Unai's mother… How is this possible?