A chess columnist ends in prison when one of his columns is mistakenly seen as a subversive attack. From there he invents a game of war and strategy and a cellmate who escapes uses it initiating a real revolution.

Students of the university of Salamanca are brutally murdered by a black masked minstrel. Alex, an architecture student who has recently moved to Salamanca discovers a pattern behind the killings; it seems as if the killer strikes regularly after the exams to free the campus from lousy students.