When the students of the National University in Mexico City go on strike, good friends Sombra and Santos begin to find interesting ways to fill their days. Their routine is interrupted by the unexpected arrival of Sombra's kid brother Tomás, who is unable to fit-in with these older slackers. When Tomás discovers that unsung Mexican folk-rock legend Epigmenio Cruz has been hospitalized somewhere in the city, he convinces Sombra and Santos that they should track him down to pay their final respects on his deathbed. But what they assumed would be a simple trip to find their childhood idol, becomes a voyage of self-discovery across Mexico City's invisible frontiers.