Three years after Figaro, the clever barber, had helped Count Almaviva steal his beloved Rosine from her guardian, Dr. Bartholo, the count has become tired of his wife and has begun to pursue other attractive women, particularly Suzanne, his wife’s maid, who is betrothed to Figaro. Suzanne informs Figaro of the count’s interest, including his plan to send Figaro on a mission to England so that he can pursue Suzanne undisturbed. Figaro vows to prevent this.

Figaro also has trouble from another source. Marceline, the count’s housekeeper, has Figaro’s note for a sum of money she had lent him; if he does not repay the money he will have to marry her. Marceline wants to marry someone, and Figaro, despite the disparity in their ages, seems the likeliest prospect. Bartholo is helping her, mostly to revenge himself on Figaro for having outwitted him.

The count’s young page, Chérubin, is fascinated by all women, especially the countess. When the count learns of this infatuation, he banishes the page from the castle and orders him to join the count’s regiment. Figaro has other ideas. He plans to dress Chérubin in Suzanne’s clothing and send him to keep a rendezvous with the count. Figaro hopes that the count will feel so embarrassed and appear so ridiculous when the trick is exposed that he will stop pursuing Suzanne. Figaro also sends the count an anonymous letter hinting that the countess has a lover. When the count bursts into his wife’s chambers in search of this lover, he finds no one but Suzanne, for Chérubin, who had been there moments earlier, had jumped out of a window. After fabricating several stories to account for strange coincidences, Figaro is delighted when the count has to beg his wife’s forgiveness for his unfounded suspicions.

Figaro does not have the chance to send Chérubin to keep the tryst with the count because the countess and Suzanne are also plotting to foil the count’s plan. After the count tells Suzanne that he will not allow her to marry Figaro unless she meets him at a pavilion that night, she and the countess concoct a plan to defeat him.

Marceline takes her case against Figaro to court. Since he wants to place obstacles in the way of Figaro’s wedding, the count himself presides at the hearing; he rules that Figaro must either repay the money to Marceline or marry her immediately. The sentence has scarcely been pronounced, however, when Marceline discovers that Figaro is her long-lost illegitimate son by Bartholo. She says the relationship explains the love that had made her want to marry him. Marceline and Bartholo finally agree to marry, though Bartholo is unhappy that his worst enemy has turned out to be his son. During the dancing to celebrate Suzanne’s and Figaro’s wedding, Suzanne passes a note to the count to set up their rendezvous. Figaro sees it and is devastated.

That night in the garden, Suzanne and the countess, dressed in one another’s clothing, prepare to spring the trap on the count. Figaro, who does not know of the women’s plan, has hidden himself in a pavilion to observe Suzanne’s treachery; Bartholo and Marceline accompany him, and he broods at length about his topsy-turvy destiny and the general injustice of society. The countess, disguised as Suzanne, meets the count and permits him to woo her, accepting money and gifts from him. The count protests his love for her and compares her favorably with his wife. Enraged at Suzanne’s apparent duplicity, Figaro approaches the supposed countess (Suzanne in disguise) and begs her favor; when he recognizes his beloved’s voice, he decides to turn her trick around and began to woo her. Suzanne slaps him soundly for his apparent duplicity. Figaro is delighted to learn that Suzanne has not played him false and that the count is actually trying to seduce his own wife.

After much confusion, during which the count discovers that everyone has observed his folly, the situation is untangled. The countess fondly forgives her husband, and the count consents to the marriages of Suzanne and Figaro, Marceline and Bartholo, and Chérubin and the gardener’s daughter. Both the count and countess give a large dowry to Suzanne, and Figaro at last has parents, a fortune, and a beautiful wife. Everyone joins in rejoicing that wit and intelligence can even the social odds.