Tío is the name given to the numerous rough statues of the Devil that protect veins of minerals in strategic places in the mineshafts. The tío is always found sitting wrapped in streamers and confetti, with horns on his head and a big, erect penis. Miners sit with him during rest periods and chew coca leaf together, smoke, and share a drink. Miners are also the “devils” who come out at Carnival to dance in the streets by the thousands, above all in the mining city of Oruro. The tío is an adaptation to mining culture of old Andean agricultural beliefs about the fertile forces of the underworld that are both terrifying and sacred. The fortunes of the mines—whether a miner finds a rich vein or suffers an accident—depends on the tío. The miners who adhere to these beliefs can be at the same time militant revolutionaries. In times of repression, they often held clandestine meetings deep inside the mineshafts, near the tío. The interior of the mine is a sort of smelter where the Devil and Marx, the Andean imaginary and capitalist exploitation are amalgamated. It is said that one can go mad or die of fright if one encounters the tío while wandering through the mine. The unsettling short story that follows, by René Poppe, who himself worked in the mines in the Siglo XX district, reflects the workers’ belief that, after years underground, the miner becomes the Devil’s double.