The bite of the scorpion on the baby of Kino and Juana sets in motion the events of the remainder of the plot.

• When Coyotito screams, his mother tries to suck out the poison and Kino's brother Juan Thomas and his family crowd the entrance to the hut to see what is wrong.
• Juana tells Kino to get the doctor.
• All those who hear Juana tell her that the doctor will not come, so the determined mother says they will go to the doctor themselves.
• A procession is formed as Juan Thomas and his wife and the children and neighbors follow Kino and Juana
• Kino stops at the gate of the doctor, who is not of Kino's race. When a servant appears, Kino tells him why they all have come.
• The doctor, of French descent, will not see the baby. He says, "Have I nothing better to do than cure insect bites for 'little Indians'? I am a doctor not a veterinary[sic]. Has he any money?"
• Because Kino does not have money, he is turned away.
• Angered at this rejection, Kino dives into the sea for a great pearl that will bring a great price.
• Kino eventually finds a beautiful, large pearl; others call it "The Pearl of the World."
• "All manner of people" become interested in Kino--"people with things to sell and favors to ask." Kino's pearl is on the minds of so many people that Kino becomes "curiously every man's enemy."
• Kino begins to plan what he wants for his son and himself in the future.
• The priest arrives, saying that he has learned of Kino's finding a great pearl.
• The doctor later arrives, excusing himself for not seeing Kino in the morning, saying he was out. He gives Coyotito some medicine.
• The neighbors begin to watch Kino and his family to see if owning the pearl changes them. 
• Kino digs a hole inside his hut, and he buries the pearl.
• A thief tries to enter the hut at night and steal the pearl; Kino fights him and the thief flees.
• Kino goes to pearl dealers in order to sell his pearl. But they will not give him what the pearl is worth; so, Kino plans a trip to the capital.
• Juana tries to throw the pearl back into the ocean, but Kino catches her and strikes her in the face with his fist. 
• As Kino walks up the brush line, he is attacked and knocked to his knees. But, Kino manages to fight the thief off and kill him.
• Kino asks his brother Juan Thomas to hide him and his family for the night because his hut has been burned.
• Kino and his family depart and hide in a cave for the night. But, because there have been men tracking him, he leaves Juana and the baby while he goes after these men.
• Kino circles around and comes upon the trackers. Just as he is in midleap, Kino hears a rifle fire. After the rifle fire, is a scream; he kills the shooter and attacks the other two and kills them. 
• When he returns to his wife and child, the baby has been shot.
• With their dead baby, Kino and Juana return to the village.
• They walk to the water's edge, and Kino throws the pearl back into the sea.