The palace of Count Almaviva near Seville. Figaro, servant to the Count, and Susanna, the Countess’ maid, are preparing to get married. Susanna tells her fiancé that the Count has given them a room close to his so he can continue to accost her with lecherous intentions. Bartolo and his housekeeper, Marcellina, appear on the scene with a contract stating that Figaro shall have to marry her if he does not pay his debts. Susanna and Marcellina then cross paths and trade insults. Next to arrive is Cherubino, the Count’s page. He is a lovestruck youth who has been expelled from the palace by the Count after being caught flirting with Barbarina, the daughter of Antonio, the gardener. The page begs Susanna to plead with the Countess on his behalf for the Count to forgive him. The Count bursts into Susanna’s room, forcing Cherubino to hide behind a chair. The Count tries to seduce the maid, but when he hears someone coming, he hides behind the chair. Cherubino slips out of his hiding place and onto the chair, and Susanna covers him with a dress. Basilio, the music teacher, enters and tells Susanna about Cherubino’s attraction to the Countess. This angers the Count, and, in a fit of jealousy, he leaps from his hiding place. He then discovers Cherubino and accuses Susanna of infidelity towards her fiancé. Figaro appears with a group of peasants who sing a song of gratitude to the Count for abolishing the droit du seigneur (his right to bed a servant girl on her wedding night). The nobleman, suspecting that they are plotting against him, reluctantly forgives Cherubino on the condition that he enlists in the army.
Countess Almaviva laments how her husband no longer loves her as he once did. Figaro and Susanna convince her to help them lay a trap for her husband to stop him lusting after Susanna: they have summoned the Count to an amorous tryst with Susanna in the gardens, at midnight, where he will be caught red-handed by his wife. But instead of Susanna, it will be Cherubino, disguised as her, at the rendezvous. The Countess and Susanna begin to disguise the page as a woman. Susanna leaves the room for a moment and the Count knocks at the door. Cherubino hides in the closet. The Count, suspicious at finding the door locked, grows even more angry when he hears noises in the closet. The Countess insists that it is Susanna inside the closet, but the Count’s suspicions are raised by his wife’s refusal to open the door, so he leaves with her in search of tools to force the closet door open. Susanna seizes this opportunity to take Cherubino’s place in the closet while he escapes through the window. When he opens the closet door, the Count is stunned to see that his wife was telling the truth. But then the gardener Antonio arrives, complaining that a man jumped out of the window and ruined his flowers, planting new suspicions in the mind of the Count. Enter Figaro, who uses his improvisational skills to try to convince the Count that it was he who had leapt through the window. But then Bartolo, Marcellina and Basilio burst in, demanding that Figaro honour his contract to Marcellina if he does not pay his debts. The Count sees the charges as a way to get rid of Figaro.
Susanna pretends to give in to the Count’s amorous advances and proposes a tryst. Figaro, who thought he was an orphan, discovers that Marcellina and Bartolo are his parents. Susanna and the Countess finish the letter summoning the Count to a rendezvous in the garden. In reality, it will be the Countess disguised as Susanna who will be waiting to give her husband a lesson. Cherubino, caught once again by the Count, is pardoned thanks to a timely intervention by Barbarina. Preparations for the wedding finally begin; the guests arrive and dance a fandango while Susanna takes the opportunity to +slip the note to the Count.
The palace gardens. Susanna and the Countess have swapped outfits. Susanna enters the left pavilion, leaving the path clear for the Countess, who takes her place. Cherubino mistakes the Countess for Susanna (as she is wearing her clothes) and declares his love for her. The Count arrives. In the confusion of the darkness he receives a kiss from Cherubino that was meant for Susanna (actually the Countess). At the same time, Figaro, lurking nearby, receives the slap that the Count meant for Cherubino. The Count, finally alone with the woman he believes to be Susanna, proclaims his love for her and gives her his wife’s ring. The Countess flees and takes refuge in the right pavilion when she hears people approaching. The Count flees into the woods. Later, when the Count returns, Figaro pretends to court the Countess (actually Susanna). The enraged Count denounces his wife’s infidelity to all and sundry. However, to the astonishment of all present, the Countess exits from the right pavilion wearing the ring that the Count had just given to the woman that he believed to be Susanna. The Count asks his wife for forgiveness and everyone rejoices at the happy ending.