Amahl, a poor, disabled shepherd boy who walks with a crutch, lives in a modest hut with his widowed mother. Though they struggle to survive, Amahl is cheerful and imaginative, often telling tall tales. As the opera begins, he tells his mother an incredible story about a star with a tail as big as a kite that he’s seen in the sky. She dismisses it as another one of his fantasies and scolds him for not helping her.

That night, as they prepare for bed, there’s an unexpected knock at the door. Amahl answers and is astonished to find three splendidly dressed kings—Melchior, Caspar, and Balthazar—traveling to see a miraculous child, guided by the very star Amahl had described. The kings explain they are seeking a place to rest for the night. Amahl and his mother welcome them into their humble home.

The villagers arrive, bringing simple gifts and food for the royal guests. They dance and celebrate. After the festivities, Amahl’s mother, overwhelmed by the gold and treasures the kings carry, secretly tries to take a small amount to help her son. She’s caught by the kings’ page, but King Melchior intervenes. Instead of anger, he shows compassion, explaining the child they seek will bring salvation to the poor and the oppressed.

Ashamed and moved by their kindness, Amahl’s mother returns the gold and wishes she had something better to offer. In a sudden moment of grace, Amahl offers his crutch as a gift for the Christ child. As he does, a miracle occurs—he is healed and can walk unaided.

The opera ends as Amahl, now cured, leaves with the kings to visit the newborn child, with his mother’s blessing.