The film is based on the short story, No oyes ladrar los perros, written by Juan Rulfo and collected in El llano en llamas. The short story tells the tale of an old man carrying his wounded (criminal) son on his back in search of help. The film has a younger father carrying his sick child on his back looking for help. Meanwhile he tells his son about what his future life will be like. The film intercuts between the story of the man and his child and the possible future of the child as a young indigenous man looking for work in Mexico City.