The main character, Gregorius, teaches classical languages at a Swiss lycée, and lives a life governed by routine.
One day, he comes into possession of a book, written by Prado, a deceased Portuguese aristocrat. Deeply absorbed by Prado's philosophical writings, he changes his life in order to discover more about Prado. He takes the train to Lisbon that same night, exploring Prado's life during Antonio de Oliveira Salazar's dictatorship in Portugal. Through Prado's book, he learns that the author was a doctor and poet who had taken up arms and fought against Salazar.
This book is something different and very interesting to read.