Kino lives a simple life with his wife Juana and their infant son, Coyotito. Their tranquility is shattered when Coyotito is stung by a scorpion, and the local doctor refuses to treat him due to Kino’s poverty. In a desperate bid to provide for his family, Kino dives for pearls and discovers an enormous, lustrous pearl, which he believes will bring prosperity and happiness.

However, the pearl becomes a source of conflict and tragedy. As news of Kino’s discovery spreads, it attracts the attention of greedy townspeople and corrupt pearl buyers who conspire to cheat him. Despite Juana’s warnings that the pearl is evil and will bring misfortune, Kino becomes obsessed with its potential wealth. He dreams of marrying Juana in a church, sending Coyotito to school, and escaping their oppressive life.

Kino’s refusal to sell the pearl at a fair price leads to escalating violence. He faces multiple attacks from those who wish to steal it, resulting in tragic consequences. In a climactic series of events, Kino kills a man in self-defense but ultimately suffers devastating losses when Coyotito is accidentally shot by trackers who mistake his cry for that of a coyote. In the end, devastated by the loss of his son and recognizing the pearl’s curse, Kino and Juana return to La Paz and throw the pearl back into the sea, symbolizing their rejection of greed and the false hopes it brought.