Figaro confides in the Countess, explaining to her that he has his own scheme to ensure that the Count does not succeed. Figaro tells Suzanne to agree to the Count’s request to meet later in the garden. Figaro does not want Suzanne to sleep with the Count; instead, she should dress up Cherubin in her clothes and send him to the meeting instead. He will be Suzanne’s representative. At the same time, Figaro says, he will work on the Count and convince the Count that the Countess is having an affair of her own. Figaro will invent an affair that will make the Count jealous, a jealousy that he will then exploit. 

The Countess reveals that she had been entertaining a similar plan. She was going to write a letter, in which she and an unspecified person would seem to be conducting an affair. Figaro is one step ahead: He already has exactly this kind of “unsigned letter” and, according to Figaro’s letter, the Countess’s mysterious lover will be present at the wedding. This, Figaro explains, will ensure that the Count wants the wedding to go ahead, so that he can catch his wife’s lover. 

Suzanne is concerned that Marceline will interfere. Figaro is not concerned about her. He believes that the Count is the biggest obstacle to the wedding, so they must ensure that it is the Count who wants them to proceed. Figaro departs to fetch Cherubin, so that Suzanne can “dress him up” to look just like her (113).

Now alone with the Countess, Suzanne reveals the love song written by Cherubin. She suggests that, rather than scold Cherubin, the Countess should make him sing the song to her. She places the song on the Countess’s lap.

Cherubin arrives, expecting the Countess to scold him. Instead, she beckons him forward and asks why he seems so downcast. Suzanne begins to dress Cherubin in her clothes as the Countess encourages him to sing his love song. He agrees, with Suzanne accompanying him on the guitar. The romantic song is dedicated to a woman whose absence makes the singer’s heart “ache with sadness” (115). The Countess is touched by the “charming” song. Suzanne works on Cherubin’s disguise.

As Suzanne exits the room to fetch a bonnet, Cherubin is left alone with the Countess. He shows her the Count’s letter, formally sending him away. The Countess notes that her husband was in such a rush that “he’s forgotten to put his seal on it” (118).

Suzanne returns with a hat for Cherubin to wear. She is pleased to see that Cherubin “makes a very pretty girl” (119), so much so that she is jealous that he looks so much better in her clothes. She finds her own ribbon wrapped around Cherubin’s arm, which—he says—he used to cover up an injury. The ribbon is now laced with blood. The Countess sends Suzanne to fetch a sticking plaster.

Cherubin sits before the Countess, looking lovingly at her as she ponders a ribbon. She is “very cross to have lost it” (120).

Suzanne returns, interrupting the heated moment. The Countess sends her away again.

Left alone again, Cherubin and the Countess talk about ribbons as keepsakes. Cherubin is sad that he will soon be sent away from the Countess. She blames Figaro and wipes the tears from Cherubin’s eyes, urging him to stop before he declares his love for her as he is “not making any sense” (121). They are interrupted by the sound of a knock.

The Count is outside his wife’s bedroom, demanding to know why the door is locked. The Countess is worried that her husband will catch Cherubin in her room after receiving Figaro’s letter about her lover. This will ruin Figaro’s plan, so she tells Cherubin to hide in the dressing room. Cherubin hides.

The Countess criticizes herself for letting this farcical situation occur.

The Count enters, noting that his wife does not “usually lock her door” (122). She also seems agitated. The Countess claims that she was simply discussing her husband’s indifference and his jealousy. The Count alludes to his wife’s possible affair, but the Countess defends herself, claiming that she would not receive another man in her bedroom. 

They are interrupted by the sound of a falling chair in the dressing room. The Countess claims to have heard nothing, then suggests that perhaps Suzanne is to blame. The Count quizzes her, insisting that she seems “perturbed.” He insists on seeing Suzanne at once, to which the Countess responds that he often insists on seeing her. She insists that there is “absolutely no foundation” for her husband’s suspicions (123).

The Count orders Suzanne to come out of the dressing room. Suzanne, overhearing him from a different room, pauses. The Countess delays, claiming that Suzanne is not wearing any clothes. As the Count and the Countess talk, Suzanne slips into the bedroom. She hides behind the curtains until the Count leaves to find an instrument with which he can open the dressing room door. The Countess goes with him; the Count locks the other doors behind him as the Countess laments this “odious proceeding.”

As soon as they have left the bedroom, Suzanne opens the dressing room door. Cherubin panics, then rushes out and leaps from the window, pausing just long enough to give Suzanne a kiss for good luck. He lands in the melon patch beneath the window.

Suzanne enters the dressing room and locks the door behind her.

As the Count returns to the bedroom, the Countess begins to plead with him to stop “such unbecoming conduct” (126). She begs for mercy, admitting that Cherubin is in her dressing room. She insists, however, that they are not having an affair and that this is a simple misunderstanding, as she and Suzanne were dressing him as a woman. This is just a “practical joke,” she says. 

The Count is enraged. He criticizes and threatens Cherubin as the Countess collapses into a chair, overwhelmed by fear and worry. At the peak of his anger, the Count opens the dressing room door and finds Suzanne.

This shocks the Count and the Countess, as Suzanne strolls into the bedroom, mocking the Count’s anger. The Count is stunned by this “disaster.” He enters the dressing room to see if there is anyone else inside.

Suzanne assures the Countess that Cherubin is “miles away.” The Countess fears that she is going to die.

The Count returns and admits that the dressing room was empty. He praises his wife as a “talented actress.” The Countess laments how much she has been changed by the Count’s actions; her husband no longer loves her, she claims, so she must withdraw to a convent. The Count turns on his wife; she admits to him that Figaro is the author of the anonymous letter that claims that she is having an affair. As they discuss her acting talents and how she was able to pretend to be concerned about who was in the dressing room, Figaro enters the bedroom.

The Countess tells Figaro that the Count has learned about the anonymous letter, which she hints should be taken as a joke rather than a plot. Figaro catches her meaning and attempts to play along with the façade, though the Countess assures him that the clever Count has worked everything out about their joke.

The conversation is interrupted by the gardener, Antonio. Already half-drunk and with a broken flowerpot tucked beneath his arm, Antonio claims that a man in a white shirt just jumped from the window and destroyed the potted plants. Figaro acts quickly. He claims that it was he who jumped from the Countess’s window. Though Antonio suggests that the offender looked more like “that skinny page” (136), Cherubin, Figaro assures everyone that it was actually him who leapt from the window.

Antonio comes to accept that Figaro is telling the truth. He hands back a piece of paper that he found in the flower bed. The paper is the Count’s unsealed letter held by Cherubin, which must have fallen from his pocket. The Count snatches it away. Suzanne and the Countess realize what has happened. Through careful hints, they manage to convey this to Figaro, who invents a story about Cherubin giving him the letter earlier so that he could ask the Count to seal it properly. Enraged, the Count tries to storm out, but Figaro stops him to ask whether the Count will go “without giving the word for [Figaro and Suzanne’s] wedding to proceed” (138).

Bazile, Marceline, and Bounce arrive. Marceline asks the Count to give his judgment on her situation with Figaro, explaining that Figaro owes her money. If Figaro cannot settle the debt, she explains to the Count, then he has promised to marry her. 

The Count sees an opportunity and calls on the court’s legal representatives to gather together in the great hall. They will determine the validity of Marceline’s claim. Bazile would also like to press a claim of his own. The Count is annoyed with Bazile, so he sends Bazile on an errand. When Bazile insists that he, as a music teacher, is above such duties, a goat herder named Grippe-Soleil volunteers. The Count sends Grippe-Soleil on the errand, but decrees that Bazile must accompany the goat herder while playing guitar as “that’s what [he’s] paid for” (140).

The Count exits, and the remaining characters complain about him. In an aside, Bazile reaffirms his own desire not to help Figaro, but to bring about his own desire to marry Marceline. As Bazile exits with his guitar, Figaro begins to sing a tune in honor of Suzanne.

As the characters disperse, the Countess is left alone with Suzanne. The Countess shares her wish that she would be able to expose her husband’s infidelity. She decides to directly confront her husband about the matter. Their previous plan has been confounded, but she makes a new plan: She will attend the meeting in the garden herself, dressed as Suzanne, so that no one will be “running any risk” of infidelity (142). The Countess tells Suzanne to tell the Count that she agrees to their meeting. She swears Suzanne to secrecy; she does not want anyone—“not even Figaro” (142)—to know about her plan.

Alone, the Countess is excited about her new scheme. She takes Cherubin’s ribbon and slips it into her pocket.

Suzanne returns and praises the Countess’s “wonderful” plan. She is hopeful that she will be able to marry Figaro after all.