Balmaseda, 1683. Pedro Urtiaga has just been poisoned. In his last hours of life he writes to his friend, Doctor Zúñiga, announcing his imminent death and begging for vengeance. Zúñiga will travel to Basque lands to find out the identity of the murderer. He will soon discover that his death is not only related with wine, but also with a game of cards that has only just been invented: mus.

Ancient legends, women in love and false appearances will all become tied up in this story - in which events relentlessly take place for the reader - told without artifice and with a clean and magnetic prose.