Twelve years before the opera begins, Prospero, Duke of Milan, was overthrown by his brother Antonio, in league with Alonso, King of Naples. Prospero and his infant daughter Miranda were set adrift in a small boat.  They landed on a remote island, inhabited only by the sprite Ariel and the monstrous Caliban, who was enslaved by Prospero after trying to seduce Miranda.

Seeking revenge for his banishment, Prospero has caused a great tempest, which has wrecked a ship carrying his brother Antonio (now Duke of Milan) and King Alonso, as well as their courts. Alonso’s son Ferdinand was separated from the others, who were safely brought ashore by Ariel at Prospero’s orders, and who now sleep on the shore. Ferdinand mourns, believing his father and the rest of his party to have drowned, until he sees Miranda, and the young couple falls immediately in love. Angered by Miranda’s infatuation with the heir to Naples’s king, Prospero paralyzes Ferdinand.

The shipwrecked courtiers awaken and discuss their miraculous salvation. Prospero orders Ariel to sow discord between them and they begin to quarrel, while Alonso, assuming Ferdinand to have drowned, mourns his son’s death. Caliban appears and tells them about the island. He is about to divulge Prospero’s name when he is silenced by the powerful magician. The courtiers search the island in vain for Ferdinand, while the unseen Prospero observes the love growing between Ferdinand and Miranda.

Caliban and two of the courtiers plot to murder Prospero, while Ariel leads everyone else on a grueling trek through the island’s forests and swamps. Antonio encourages Sebastian, who is Alonso’s younger brother, to murder the King. Their plot is revealed by Ariel, who then appears in the guise of a harpy and explains that their travails are the result of their having banished Prospero to the same island twelve years earlier. Miranda and Ferdinand announce their love to Prospero, who reluctantly blesses them. Ariel tells Ferdinand that he will soon be reunited with his father. Satisfied that the courtiers have been sufficiently punished for their misdeeds, Prospero appears to them. They ask his forgiveness, which he grants. Prospero conjures up their now-undamaged ship, on which they can sail back to Europe, and announces that he will return to Milan to rule, with a stop in Naples for the wedding of Miranda and Ferdinand. Ariel and Caliban remain on the island.