Sir John Falstaff is drinking at the Garter Inn when Dr. Caius storms in, accusing Falstaff’s sidekicks, Bardolph and Pistol, of robbing him. Falstaff dismisses the doctor but scolds his companions for their inept thievery. He tells them his newest money-making scheme: he has written love letters to two rich married women, Alice Ford and Meg Page. He plans to romance them both and help himself to their husbands’ fortunes. Bardolph and Pistol refuse to help, claiming this scheme offends their honor.
Falstaff mocks the very concept of “honor” and kicks them out.
At Ford’s house, Alice and Meg discover that Falstaff has sent them identical letters. Together with Mistress Quickly and Alice’s daughter, Nannetta, they resolve to punish Falstaff. Meanwhile, Bardolph and Pistol tell Alice’s husband, Ford, of Falstaff’s plan. Each group launches a scheme: the women will send Quickly to entice Falstaff into a rendezvous with Alice, while Ford will visit Falstaff in disguise to check up on his wife’s fidelity.
Back at the Garter Inn, Bardolph and Pistol pretend to seek Falstaff’s forgiveness. Quickly arrives and assures Falstaff that he has conquered the ladies’ hearts and that Alice expects him to visit this afternoon. After Quickly leaves, Bardolph and Pistol introduce a “Mr. Brook” (really Ford in disguise), who rhapsodizes about his love for the chaste Alice Ford and asks the worldly Falstaff to seduce her in the hope that she will then succumb to Brook. Falstaff boasts that he already has an assignation with Alice—and Ford can barely control his jealousy.
Alice, Meg, and Nannetta prepare for Falstaff’s visit. Nannetta, in love with Fenton, is weeping over Ford’s determination to marry her off to Dr. Caius, and Alice promises to protect her. Falstaff enters and woos Alice, but they are disturbed by Quickly and Meg, who pretend that Ford is coming in a jealous rage. Soon after, Ford actually does appear, followed by Bardolph, Pistol, Dr. Caius, and Fenton. They ransack the house looking for Falstaff, whom the ladies have hidden in a large laundry basket. The men, returning from their unsuccessful search, hear a loud kiss, but a search reveals only Fenton and Nannetta. Ford separates the two lovers, and Alice calls everyone to watch as the merry wives dump Falstaff with the dirty laundry out of the window into the Thames.
In the courtyard outside the Garter Inn, Falstaff tries to dry off. Quickly arrives and assures him that Alice was distressed by the outcome of their meeting. Alice’s new instructions are for Falstaff to dress as the Black Hunter and meet her in Windsor Forest at midnight. Falstaff takes the bait for this next humiliation and exits with Quickly. Ford tells Dr. Caius his own plan: when they are in disguise in the forest, Ford will marry Nannetta, disguised as the Queen of the Fairies, to Dr. Caius. Quickly overhears Ford’s conversation and leaves to tell Alice.
In Windsor Forest, Fenton meets Nannetta. Alice interrupts, giving Fenton a disguise that will allow the young lovers to circumvent Ford’s plan. Falstaff arrives to woo Alice one more time, but all the others appear in fantastical disguises, and taunt and torment him. Eventually, Falstaff catches on and forgives them all for humiliating him. Ford suggests that they end the evening with a wedding. Alice asks if a second couple might receive his blessing as well, and Ford agrees. Two veiled couples come forth. After the ceremony, Ford discovers that he has married Nannetta to Fenton and Caius to Bardolph. Ford and Caius are initially chagrined, but soon relent and pronounce their blessings on the young couple. Falstaff teaches Ford and Caius to be good losers: “All the world’s a joke, man is born a joker, and he who laughs last, laughs best.”