Claudio is a high school student who sits in the back row. He does not speak, he does not participate, he is not problematic, he does not stand out, except in Mathematics. Each class becomes more unbearable until Xermán, the language and literature teacher, sets the task of writing an essay about the weekend. After a while, Claudio begins to transform into an observant, imaginative individual who writes the lives of others in a serialised story for a single reader. The story shared by pupil and teacher becomes an increasingly dangerous game for them and for those around them. A game played on two boards: life and literature.