Three years ago, Figaro helped Count Almaviva to marry Rosina, whom he stole from Dr Bartolo.
It is Susanna and Figaro’s wedding day. Susanna tells Figaro that the Count is propositioning her. Figaro is appalled that his master would dare seduce her and that he might reinstate the old tradition of droit de seigneur. Marcellina and Dr Bartolo arrive at the house looking for the Count. They want to stop the wedding. Marcellina has a contract which states that Figaro must repay money that he owes her, or marry her himself.
Cherubino, the pageboy, has been dismissed for being caught alone with Barbarina, the gardener’s daughter. He hides until the Count catches him and sends him off to Seville to join the army. Figaro, however, ensures that Cherubino remains close by. He has a plan.
The Countess is upset that her husband is chasing other women, including Susanna, her servant. She is in mourning for her life.
Figaro’s plan is twofold. Firstly, he has sent the Count an anonymous letter to say that the Countess will be meeting a lover this evening. Secondly, he asks Susanna to lure the Count into the garden after the wedding. Figaro will make Cherubino take Susanna’s place, dressed as a girl, so that the Count will be humiliated. The Countess agrees to the plan.
After receiving the anonymous letter, the Count returns from hunting to confront his wife, interrupting her just as she is dressing Cherubino as a girl for the evening’s assignation. Cherubino hides in a cupboard, and jumps out of the window. The Countess relents and explains the plan to her husband, saying that Figaro wrote the letter.
Figaro denies writing the letter, until they come across the gardener, Antonio, who tells the Count that someone has jumped out of the window. Figaro claims it was he who jumped out of the window. Marcellina and Bartolo arrive with the contract, which the Count endorses. Chaos ensues; the wedding cannot happen. Some people are thrilled, others devastated.
The Countess has a new plan: she and Susanna will dress up as each other, and she – rather than Cherubino – will be at the assignation with the Count. Susanna, therefore, must proposition the Count, which she duly does.
The Count and Don Curzio, a judge, decide that Marcellina’s contract shall stop the wedding. Through his protestations, Figaro discovers that he is actually Bartolo and Marcellina’s illegitimate son. Restored to his parents, Figaro and Susanna can finally get married – a double wedding with Bartolo and Marcellina.
Then Antonio finds Cherubino, who has been hiding (dressed as a girl) at his house. Barbarina asks the Count to let her marry Cherubino. He is forced to agree to this.
All three weddings can finally take place! During the ceremony, Susanna passes the Count a love letter with her pin attached to it. The letter gives the details of where they are to meet later that evening.
After the wedding party, neither Figaro nor the Count knows about the Countess’s plan. Figaro finds the pin, and believes that Susanna is going to meet the Count. He leaps to the conclusion that she is unfaithful. Susanna teases him, pretending to wait for her lover. Then she and the Countess swap clothes.
The Countess (disguised as Susanna) enters the garden for her meeting with the Count, who, after rescuing her from the kisses of Cherubino, is thrilled to see her. Figaro watches all this and seethes.
Susanna (dressed as the Countess) arrives; halfway through telling her that her husband and his wife are together, Figaro realizes it is Susanna to whom he is speaking. He pretends to seduce the ‘Countess’. Susanna hits him. She eventually realizes that Figaro was joking, and when the Count comes back in, they play out a fake love scene to enrage him. The Count calls everybody to witness his wife’s scandalous behaviour. It is not until the real Countess reveals herself that the Count realizes what has happened and begs his wife’s forgiveness.