Malvolio finds the letter on the garden path and falls for the trick as he is watched gleefully by the group led by Maria and Sir Toby. Malvolio is socially and sexually ambitious Maria realizes this and writes a letter purporting to come from the Countess Olivia, making Malvolio believe that his lady is in love with him and wishes to marry him the letter also asks him to be firm and obstinate with her uncle, Sir Toby, to be arrogant to the other servants, and to dress in yellow stockings and go cross-gartered, and to smile all the time when he is near her.

Thus, he has already gotten on the wrong side of Maria, Feste, and Sir Toby, and the plot involving their determination to take their revenge upon him provides the best humor of the play. His colossal vanity and egotism get between him and everything that he sees and does. Then outside of all of these groups stands Malvolio, Lady Olivia's puritanical steward. Through Feste, all of the groups are connected by his free movement from one group to another as he is equally at home singing for Duke Orsino, or proving Lady Olivia to be a fool for so excessively mourning for her brother, or in planning a trick with Sir Toby. Then there is the merry group of pranksters, gullers, and tricksters, led by Sir Toby Belch and Maria this group also includes Sir Andrew Aguecheek (who is included because his income supports the other members of this group), Fabian, and Feste, the Clown.

Both Viola and Sebastian are, of course, later absorbed into the nobility of Illyria. Then there is the group of shipwrecked personages centering on Viola and Sebastian, the twins, and their friends, Viola's sea captain who fades from the action, and, more important, Antonio, who plays a significant role later in the comedy.

There is, first, the group centering around the ducal nobility of Illyria: this group consists of Duke Orsino and his attendants, who open the play, and the Countess Olivia, who is the main topic of discussion of the opening scene. Regardless of the exact number of plots and subplots, however, the main thing is that they are all woven together with immense skill to ultimately compose a single pattern or tapestry.

Various critics divide Twelfth Night into various types of plots and/or subplots.

William shakespeare 12th night