The film follows a fourteen-year-old Bolivian boy named Basilio Vargas who along with his twelve-year-old brother Bernardino work in the mines near the city of Potosí.

The film includes many subtle realities of the miner's lives such as the need to chew coca leaves to numb the pain of hunger and the long shifts they work regardless of age.

The workers often give offerings such as coca leaves, alcohol, cigarettes and perform sacrifices, such as slaughtering a llama and applying its blood to the mine entrance to appease a makeshift statue of "Tio".

Each mine has its own Tio which all of the workers pray to upon entering so that they may find a good vein of silver and so that they may be granted protection from explosions, toxic gas, silicosis, and falling rocks.

The local Catholic priest is unable to tame these fears of “Tio” although the workers often pray at the church before entering the mine, upon observing the miners attending Mass, the local priest said that when he looked into the face of the miners he "saw Christ dying".