Teodoro Golfín, a skilled eye surgeon, makes his way through the north of Spain in search of the mines of Socrates at the recommendation of his brother, Cárlos, who is a friend to one of the proprietors of the mines. He receives directions to the mines from the nearby townspeople of Villamojada. As he walks, he realizes he has lost his way. When he reaches an abyss where he can proceed no further, he stops to lament his circumstances aloud. Suddenly, he hears Nela’s beautiful singing voice in the distance though he does not know its origins at first. When he calls out to her, she does not answer. Instead, a dog named Choto runs up to Teodoro with a young blind boy, Pablo, not far behind. Pablo, the only son of the wealthy Francisco Penáguilas, tells Teodoro that he is near the mines of Socrates but that the entrance is in another direction. He offers to guide Teodoro to the entrance as he is highly familiar with the mines. Teodoro is skeptical of Pablo’s ability to navigate given his lack of sight, but the boy insists that he has gone from one end of the mine to another before with the help of Choto and a walking stick when his friend, Nela, is not around.