A ship is caught in a powerful storm, there is terror and confusion onboard, and the ship is shipwrecked. But the storm is a magical creation carried out by the spirit Ariel, and caused by the magic of Prospero, who was the Duke of Milan, before his dukedom was usurped and taken from him by his brother Antonio (aided by Alonso, the King of Naples). That was twelve years ago, when he and his young daughter, Miranda, were set adrift on the sea, and eventually stranded on an island. Among those onboard the shipwreck are Antonio and Alonso. Also on the ship are Alonso's brother (Sebastian), son (Ferdinand), and "trusted counsellor", Gonzalo. Prospero plots to reverse what was done to him twelve years ago, and regain his office. Using magic he separates the shipwreck survivors into groups on the island:
- Ferdinand, who is found by Prospero and Miranda. It is part of Prospero’s plan to encourage a romantic relationship between Ferdinand and Miranda; and they do fall in love.
- Trinculo, the king’s jester, and Stephano, the king’s drunken butler; who are found by Caliban, a monstrous figure who had been living on the island before Prospero arrived, and who Prospero, adopted, raised and enslaved. These three will raise an unsuccessful coup against Prospero, acting as the play's 'comic relief' by doing so.
- Alonso, Sebastian, Antonio, Gonzalo, and two attendant lords (Adrian and Francisco). Antonio and Sebastian conspire to kill Alonso and Gonzalo so Sebastian can become King. At Prospero's command Ariel thwarts this conspiracy, and later in the play Ariel confronts the three nobles (Antonio, Alonso and Sebastian), causing them to flee in guilt for their crimes against Prospero and each other.
- The ship's captain and boatswain are asleep until the final act.
Prospero betroths Miranda to marry Ferdinand, and instructs Ariel to bring some other spirits and produce a masque. The masque will feature classical goddesses, Juno, Ceres, and Iris, and will bless and celebrate the betrothal. The masque will also instruct the young couple on marriage, and on the value of chastity until then.
The masque is suddenly interrupted when Prospero realizes he had forgotten the plot against his life. He orders Ariel to deal with this. Caliban, Trinculo, and Stephano are chased off into the swamps by goblins in the shape of hounds. Prospero vows that once he achieves his goals, he will set Ariel free, and abandon his magic, saying:
- I’ll break my staff,
- Bury it certain fathoms in the earth,
- And deeper than did ever plummet sound
- I’ll drown my book.
Ariel brings on Alonso, Antonio and Sebastian. Prospero forgives all three, and raises the threat to Antonio and Sebastian that he could blackmail them, though he won’t. Prospero’s former title, Duke of Milan, is restored. Ariel fetches the sailors from the ship; then Caliban, Trinculo, and Stephano. Caliban, seemingly filled with regret, promises to be good. Stephano and Trinculo are ridiculed and sent away in shame by Prospero. Before the reunited group (all the noble characters plus Miranda and Prospero) leaves the island, Ariel is told to provide good weather to guide the king's ship back to the royal fleet and then to Naples, where Ferdinand and Miranda will be married. After this, Ariel is set free. In the epilogue, Prospero requests that the audience set him free— with their applause.