Act I
In a room they have been allocated, Figaro and Susanna, servants to Count and Countess Almaviva, are preparing for their wedding. Susanna is concerned that the room is too close to the Count’s chamber and explains to Figaro that Almaviva is pursuing her. Figaro vows to thwart the Count’s plans. Once Figaro leaves, Dr. Bartolo and Marcellina enter. Marcellina is determined to marry Figaro, while Bartolo is angry at him for making a fool of him in the past. When Susanna returns, she and Marcellina are sarcastically polite to each other.

The page Cherubino enters, seeking advice from Susanna, as Count Almaviva caught him alone with the gardener’s daughter. Almaviva arrives, and Cherubino hides. The Count attempts to seduce Susanna, but is himself forced to hide when yet another person arrives. It’s the music teacher Don Basilio, who mentions Cherubino’s crush on the Countess. In a rage, the Count reveals himself to an amused Basilio. He becomes even more enraged when he discovers Cherubino and realizes that the boy has overheard him propositioning Susanna.

Figaro returns, accompanied by the entire household, who praise the Count. Put on the spot, the Count is forced to bless the marriage of Figaro and Susanna. To get rid of Cherubino, he gives the boy a military commission, telling him to report for duty immediately. Figaro and Susanna commiserate with Cherubino.

Act II
In her bedroom, Countess Almaviva mourns the loss of her husband’s love. Susanna tells the Countess that she and Figaro have a plan: Almaviva will receive an anonymous letter informing him that his wife has taken a lover. At the same time, Susanna will set up a rendezvous with Almaviva, but will send a disguised Cherubino in her place.

Cherubino enters with a song of love for the Countess and a commission letter that the Count forgot to seal. He is taken aback when the women begin to dress him in women’s clothes. After Susanna steps into an adjoining room, the Count knocks on the locked bedroom door. Cherubino hides in the dressing room while the Countess lets in her husband.  Almaviva is instantly suspicious and demands entry into the locked dressing room, but the Countess refuses to open it, claiming Susanna is inside trying on her wedding dress. Almaviva leaves the room to get a crowbar, taking the Countess with him. Susanna helps Cherubino escape through the window before taking his place in the dressing room. The Count and Countess return, and the Countess confesses everything to her husband. She is shocked when Susanna exits the locked dressing room. Almaviva begs forgiveness for his suspicions.

Figaro arrives to gather everyone for the wedding. He is followed by the gardener Antonio, who is upset that someone jumped from the Countess’s balcony and crushed his flowers. With prompting from the women, Figaro claims it was he who jumped. The gardener shows him Cherubino’s dropped commission, which Figaro claims he was holding to get the Count’s seal. Marcellina, Bartolo and Basilio enter, and Almaviva is delighted to hear their claim that Figaro is obliged to marry Marcellina to pay off an outstanding debt.

Act III
Later that day, Susanna approaches Count Almaviva. He once again asks her to meet him in the garden, and she agrees. He is overjoyed, but becomes enraged when he overhears Susanna conspiring with Figaro. Marcellina, accompanied by the lawyer Don Curzio, demands that Figaro pay his debt or marry her. Figaro replies that he can’t marry without the consent of his parents, for whom he’s been search for years, having been abducted as a baby. When he reveals a birthmark on his arm, Marcellina and Bartolo recognize the mark as belonging to their son, and the three joyfully reunite. Figaro embraces his long-lost mother as Susanna enters. She misunderstands the embrace and rages at Figaro. Marcellina explains the situation, and everyone is happy except the Count.

The Countess dictates a letter from Susanna to the Count, confirming their meeting that evening in the garden. Cherubino, now dressed as a girl, appears with Barbarina, daughter of Antonio. The Count and Antonio arrive, and Antonio reveals Cherubino’s disguise. Barbarina persuades the Count to let her marry Cherubino. The household assembles for Figaro and Susanna’s wedding. During the dancing, Susanna slips the Count her letter.

Act IV
In the garden later that night, Barbarina despairs that she has lost the pin the Count has asked her to take back to Susanna. When Figaro and Marcellina appear, Barbarina tells them about the pin. Thinking that Susanna is unfaithful, Figaro curses all women. He hides when Susanna and the Countess arrive, each dressed as the other.  Alone, Susanna sings of love, knowing that Figaro is listening to her. She then hides in time to see Cherubino try to kiss the disguised Countess. The Count declares his love for Susanna, who is really the Countess, while Figaro tells the Countess, who is really Susanna, about the tryst. Susanna forgets to disguise her voice, and Figaro figures out it is she under the Countess’s cloak. Susanna and Figaro embrace and are seen by the Count, who explodes with rage. At that moment, the real Countess steps forward and reveals her identity. Ashamed, the Count asks her pardon. She forgives him, and the entire household celebrates the day’s happy ending.