Arsenio Silvane, a professor of Medieval and Renaissance Literature at the University of Santiago de Compostela, disappears mysteriously while attempting to recover valuable medieval codices and incunabula, as well as other documents, drawings, and engravings stored at the Monastery of Fontsanta. He hopes to make these valuable records available to scholars and researchers as well as to the general public. When Luisa, a friend and former student of the professor´s-now a literature professor herself at the University of Lugo-learns of Silvane´s disappearance, she alerts Tomás, one of his students. Tomás and Luisa immediately decide to travel to the Monastery of Fontsanta, where they speak to several monks, but the only information they are able to obtain is that the professor visited the monastery for a few days and then left.