By order of Duke Theseus, Demetrius must marry Hermia, even though he actually loves Helena. At the same time Hermia is in love with Lysander. The four lovers escape from the town. In a forest nearby a group of tradesmen are rehearsing a play to celebrate the wedding. Titania (the Fairy Queen) has argued with Oberon (the Fairy King) over an Indian boy. In a masque Titania's retinue of fairies entertains her with music before teasing a drunken poet who has entered the forest.
Oberon and Puck (his right-hand fairy) prepare a love potion distilled from a flower. In the second masque Titania's fairies sing to her, before she is lulled to sleep by Night, Mystery and Secrecy. Puck then administers the love potion to Titania and to the lovers.
Lysander and Demetrius are now both in love with Hermia. The tradesmen rehearse and one of them, Bottom, is turned into an ass by Puck. Titania awakes and falls in love with him. She entertains him with a masque of love in which two rustics, Coridon and Mopsa, flirt with each other.
Oberon restores the true lovers back to each other, Bottom returns to human form, and Titania is released from her enchantment. Oberon and Titania's reconciliation (and his birthday) are celebrated in a masque of the seasons.
Duke Theseus discovers the lovers and agrees to them marrying as they wish. Oberon and Titania appear.
In the final masque - a celebration of the state of matrimony - the goddess Juno blesses the lovers and a Chinese entertainment takes place, followed by a monkey dance, before Hymen, god of marriage, draws the proceedings to a close.