Itxaso is 17 and lives in Mexico. However, when her mother dies, she has no option but to move to a coastal village in the Basque Country to live with her father Mikel. Mikel is a former surf champion who runs a small school. He is a man that Itxaso doesn't know and that she will be forced to get along with no matter how different they are.

In 1543, at the University of Salamanca, in Spain, Fray Antonio Román, an Augustinian monk who spreads humanist ideas, considered heretical, among his more inquisitive students, a clandestine group of four led by the brilliant novice Luis de León, mysteriously dies in unspeakable circumstances. In the present day, the historian Lara Cabanes is hired to find out if the monk was murdered, as is suspected and she is told, but the task will not be easy to achieve.