Generally considered the last play written by William Shakespeare, The Tempest is remarkable for being one of only two plays by Shakespeare (the other being Love’s Labor’s Lost) whose plot is entirely original. Though the play draws on travel narratives of the period and contains echoes of other writings (Ovid's Metamorphoses, Virgil's Aeneid, and Montaigne’s Of the Cannibals among them), The Tempest remains Shakespeare's own fantastical invention.
On a ship bound for Italy, Alonso, the King of Naples, is returning from his daughter's wedding in Tunis. He is accompanied by Ferdinand (his son), Sebastian (his brother), Antonio (the Duke of Milan), and Gonzalo (a trusted Councillor). The King’s ship is caught in a storm at sea, its passengers and crew facing certain death as the vessel splits apart.
On a nearby island, Miranda discovers that her father Prospero, the former Duke of Milan, has created the tempest through his use of magic. Prospero tells Miranda that the time has come for her to learn the story of her past and how they came to live on this island:
Twelve years ago Prospero was Duke of Milan. Engaged in his books, Prospero withdrew more and more into his studies, leaving the management of his state to his brother Antonio. Eventually, with the help of King Alonso and his brother Sebastian - inveterate enemies of Prospero - Antonio usurped the dukedom for himself. Prospero and his baby daughter Miranda were put to sea in a rotten boat. They were secretly aided by the kind Gonzalo who supplied the two with minimal provisions and Prospero’s books. Father and daughter landed on a distant island once ruled by the witch Sycorax but now inhabited only by her son, Caliban, and Ariel, a spirit (in addition the assorted lesser spirits of the island.)
For the past twelve years Prospero has ruled the island and its two inhabitants by the use of magic arts derived from his studies. His daughter Miranda has grown up seeing no other human being. Prospero tells Miranda that fortune has brought his enemies close to the island and that he has used his powers to raise the storm which shipwrecked them. He assures her that no real harm has come to the survivors.
The shipwrecked travelers have been brought to shore, and separated into different parties. At Prospero's bidding, the invisible Ariel directs their wanderings.
Before Miranda is able to see anyone from the ship, she and Prospero visit the now enslaved Caliban, who has been bound into service by Prospero since he tried to rape his daughter. Next, the spirit Ariel leads Ferdinand, the King's son, to Prospero's cell, where he and Miranda fall in love. Prospero decides to test Ferdinand through hard physical labor.
In another part of the island, the King of Naples searches for his son, although fearing him to be drowned. When Ariel puts the King and Gonzalo under a spell of sleep, Sebastian and Antonio plot to kill him and seize the crown.
Elsewhere, the King’s jester, Trinculo, and drunken butler, Stephano, encounter Caliban and are persuaded by him to kill Prospero so that they can rule the island.
As young Ferdinand continues in his labors, the King’s royal party encounters a mysterious banquet set forth by Ariel and his spirits. Ariel appears in the guise of a harpy, accusing Alonso, Antonio, and Sebastian of their wrong-doings against Prospero. He reveals that their own evil behavior has brought them to the island, and urges them to seek forgiveness and a clean life.
Satisfied that Ferdinand has met all his challenges, Prospero presents the young couple with a betrothal masque celebrating chastity and the blessings of marriage. The masque ends abruptly when Prospero remembers Caliban's plot to murder him.
Though the threat of Caliban is near, Ariel manages to distract him, Stephano, and Trinculo long enough to keep Prospero safe. As Prospero's plans draw to their climax, he vows that upon their completion he will abandon his magic arts. Ariel brings Alonso and his followers to Prospero, who dons his old royal garb, revealing his true identity. Prospero reunites the passengers of the ship, whose vessel is now safe and whole in harbor. Prospero forgives those who have betrayed him, and the rift between Naples and Milan is healed.
Prospero grants Ariel his freedom, and prepares to leave the island.