In the garden of Olivia’s house, Sir Toby, Sir Andrew, and Maria—along with Fabian, one of Olivia’s servants—prepare to play their practical joke on Malvolio. Maria has written a letter carefully designed to trick him into thinking that Olivia is in love with him. She has been spying on him and knows that he is now approaching. She drops the letter in the garden path, where Malvolio will see it. She exits, while the three men hide among the trees and shrubbery.

Malvolio approaches on the path, talking to himself. He speaks of Olivia: it seems that he already thinks it possible that she might be in love with him. He is deep in a fantasy of what it would be like to be Olivia’s husband and the master of her house. He would have power over all the other servants and even over Sir Toby. Sir Toby and the others can’t help jeering at Malvolio’s pride from their hiding place, but they do it softly so that he will not overhear them and realize that they are there.

Malvolio spots the letter lying in the garden path. He mistakes Maria’s handwriting for Olivia’s, as Maria has predicted, and Malvolio thinks that the letter is from Olivia. Apparently, Maria sealed the letter with Olivia’s sealing ring to make the letter look even more authentic. To Sir Toby’s pleasure, Malvolio decides to read it aloud.

The letter is addressed to “the unknown beloved” and contains what seems to be a riddle about love (II.v.92). It suggests that the writer is in love with somebody but must keep it a secret from the world, though she wants her beloved to know about it. The first part of the letter concludes by saying that the beloved’s identity is represented by the letters M.O.A.I. Malvolio, naturally, works over the message in his mind until he has made it mean that he is the beloved (he notes, for instance, that all four of the letters appear in his own name). Sir Toby and the rest laugh at him from behind the bush.

Once he has convinced himself that Olivia is in love with him, Malvolio reads the second half of the letter. The mysterious message implies that the writer wishes to raise Malvolio up from his position of servitude to one of power. But the letter also asks him to show the writer that he returns her love through certain signs. The letter orders him to wear yellow stockings, “go cross-gartered” (that is, to wear the straps of his stockings crossed around his knees), be sharp-tempered with Sir Toby, be rude to the servants, behave strangely, and smile all the time. Jubilantly, Malvolio vows to do all these things in order to show Olivia that he loves her in return.

After Malvolio leaves, Sir Toby remarks that he “could marry this wench [Maria] for this device. . . . And ask no other dowry with her but such another jest” (II.v.158–160). Maria then rejoins the men, and she, Sir Toby, and Fabian have a good laugh, anticipating what Malvolio is likely to do now. It turns out that Olivia actually hates the color yellow, can’t stand to see crossed garters, and doesn’t want anybody smiling around her right now, since she is still officially in mourning. In other words, Malvolio is destined to make a great fool of himself. They all head off together to watch the fun.

The practical joke played on Malvolio raises themes which, by now, are familiar: the instability of identity, the importance of clothing in establishing one’s identity and position, and the illusions and delusions that we let ourselves fall into in the name of love. Like everyone else, from Orsino to Viola, Malvolio falls victim to the allure of romance. Despite his outward puritanism, he is as much a romantic as anyone—although his fantasy of marrying Olivia has as much to do with class-related ambition as it does with infatuation.

Malvolio’s desire to rise above his class spurs his self-delusion, but it also explains why Sir Toby and the others find his fantasy so ludicrous. Malvolio is an unsuitable match for Olivia not only because of his unattractive personality but also because he is not of noble blood. He is a commoner, while Olivia is a gentlewoman. As such, that Malvolio would imagine Olivia marrying him seems obscene to them. We may recall how interested Olivia is earlier to find out from young Cesario, on whom she has a crush, that he is a “gentleman”—meaning that he is of noble birth (I.v.249). In the class system of Shakespeare’s time, it would have seemed very strange for a noblewoman to marry below her rank.

Significantly, Malvolio’s fantasy of becoming Olivia’s husband involves changing his clothing: he imagines himself “in my branched velvet gown”—the garb of a wealthy noblemen, not of a steward (II.v.42–43). The letter also asks him to alter his clothing at the same time that he changes his personality. Just as the cross-dressing habits of Viola, the play’s central character, suggest a link between clothes and gender roles, so Malvolio’s ideas about what he will wear as an aristocrat suggest a connection between wardrobes and social hierarchies. Outward appearances, it seems, can shape reality—or so Malvolio imagines. Of course, just as Viola remains a woman beneath her clothes, Malvolio’s fantasies of velvet gowns and yellow stockings will do nothing to change his place in society.

Maria’s riddle, in which she plays with the letters of Malvolio’s name, is meant to be both obvious and ambiguous. Clearly, Malvolio is supposed to decide that it refers to him, but it also allows us to watch him wrench the evidence around to arrive at the conclusion at which he so desperately wants to arrive. Various critics have wondered whether there is any further meaning in the letters M.O.A.I., other than their obvious status as letters pulled out of Malvolio’s name, but no widely accepted answers have been put forward.

Malvolio’s comments upon recognizing what seems to be Olivia’s handwriting, however, do contain an obscene pun—about which Malvolio is evidently not supposed to be aware. Examining her handwriting, he notes, “[T]hese be her very c’s, her u’s, and her t’s, and thus makes she her great P’s” (II.v.78–79). C-U-T, or “cut,” was a Renaissance slang term for the vagina, and “thus makes she her great P’s” strongly suggests a reference to penises.