At the Garter Inn, Sir John Falstaff is confronted by Dr. Caius who complains that Falstaff’s henchmen, Bardolfo and Pistola, made him drink too much and picked his pocket. Falstaff refuses to make amends, and Bardolfo and Pistola deny everything. The furious Caius storms out. Falstaff discloses his latest money-making plot: he has written the same love letter to two different married women, Alice Ford and Meg Page, who control their rich husbands’ money. He plans to woo them get their money. Bardolfo and Pistola refuse to deliver Sir John’s letters on ground of honor. Falstaff discharges the two ruffians from his service, but not before calling them cowards and lecturing them about the uselessness of honor.
At Ford’s house, Mistress Ford and Mistress Page compare the two letters from the ridiculous fat knight and, along with Nannetta (Alice Ford’s daughter) and their gossipy neighbor, Dame Quickly, they plot a comic revenge. As they leave, Ford, Bardolfo, Pistola, Caius, and Fenton enter, burning with rage. Ford has found out about Falstaff’s plan to seduce his wife. Nannetta and Fenton meet briefly – they are in love, but unfortunately her father wants her to marry the foolish Dr. Caius. The ladies send Dame Quickly to invite Sir John to a meeting with Alice. Ford plans his own revenge: under an assumed name he will go to Sir John and set his trap for Falstaff.
Back at the Garter Inn, Bardolfo and Pistola pretend to be sorry and beg to return to work. Mistress Quickly arrives. She tells Sir John that both ladies are in love with him, she suggests that he visit Alice when Ford is away from the home – between two and three o’clock. When she leaves, Falstaff congratulates himself. Moments later “Signor Fontana” (Ford in disguise) arrives and offers to pay Falstaff to seduce Alice so he will have an easier time doing the same thing himself. Falstaff agrees happily and reveals that he already has an appointment with Alice that very afternoon. Ford is shocked; and when Falstaff leaves to change, Ford denounces all women for their unfaithfulness. Sir John returns, and they leave together.
Back at Ford’s house, Quickly hurries in to tell the ladies that Falstaff has fallen for the plot and will be there any minute. Alice calls her servants to get everything ready, including a big basket of dirty laundry that they are to empty in to the river later. After promising the tearful Nannetta that she won’t have to marry Caius, the ladies prepare for Falstaff’s visit. He arrives, but his wooing is interrupted when Quickly arrives to say that Meg is coming. Falstaff hides behind a screen. Meg, trying not to laugh, says that Ford suspects that Alice has a man hidden in the house and is coming to kill him. Quickly then rushes in to announce that Ford actually is coming to the house. Ford enters angrily and he and his men look everywhere but find nothing. They rush off to search the rest of the house while Meg and Quickly help Falstaff into the laundry basket and Fenton and Nannetta hide behind a screen. Ford returns, remembering that they have yet to check behind the screen, and discovers the two young lovers. He dashes off to renew the search for Falstaff as Alice tells her servants to take the laundry basket away. As Sir John is dumped into the river, Ford, Alice, and the others laughingly enjoy Falstaff’s humiliation.
Outside the Garter Inn, Falstaff is “delivered” from the river by local fishermen. Depressed, Falstaff orders wine to revive his dampened spirits. His disposition improves when Dame Quickly arrives to say that Mistress Ford is sorry for what happened and that she wants to meet him at midnight at Herne’s Oak in Windsor Forest. He is to come disguised as the Black Huntsman with antlers tied to his head. They leave to make plans, and Alice tells the tale of the Black Huntsman to prepare everyone for the evening’s masquerade. Ford promises Caius that he can marry Nannetta that night and urges him to wear the right disguise. Fortunately, Quickly overhears their conversation.
In Windsor Park, Fenton sings of his love. Everyone is hidden when Falstaff comes to meet Alice, but they are interrupted by Meg calling for help. Sir John is frightened when he hears strange noises. A whole troop of fairies arrives with Nannetta who is disguised as their queen. Quickly come with a group of witches and goblins. They all join in tormenting the terrified Falstaff who finally discovers the truth. Caius is tricked into “marrying” the disguised Bardolfo, and Ford must five his blessing to Nannetta and Fenton. Nearly everyone has been tricked, and they all agree that the world is a crazy place.