Hyacinth, a former matador who lives miserably with his nephew Pepote, receives a letter reminding him that, as agreed a few days before, he must participate in a bullfight to be held that same afternoon.
The owner of a building tyrannizes his immigrant tenants. Transformed into a dog by an old woman's curse, he experiences all the hardships of his situation; when a child's affection turns him back into a man, his soul is radically changed.
By chance, Miguel el Tarta becomes a potential boxing champion. Manipulated by Manolo, his opportunistic and cynical best friend, and several unscrupulous individuals, Miguel is thrown into the ring, where he tries to fight with more enthusiasm than technique.
