The Protagonist – Viola
When Viola (who disguises herself as "Cesario") washes up on shore after being saved from a harrowing ship-wreck that's separated her from her twin brother, it's pretty clear the play is interested in putting Viola's life back together again. Even when Viola engages in some very self-destructive behaviour (falling for a moody, self-centred Duke and then agreeing to deliver the guy's love notes to another woman), we can't help but cheer her on.
The Antagonist – Malvolio
The "ill-willed" Malvolio, who rains on everybody's parade, is definitely the villain of our play. He's haughty and likes to tattle on everybody. He also somehow manages to imprison the sea captain, who is holding Viola's "maiden weeds" (her dress). This is a bit of a problem, since Duke Orsino says he wants to marry Viola after she changes clothes and starts to look more like a girl. We never really worry that Malvolio will actually ruin Viola's chances for happiness – the minor costume glitch is more of a delay than a permanent problem. Still, Malvolio is a total pain and he never really goes away. In fact, as he runs off stage, he promises to get revenge for the mean prank that made him look so foolish.
The Guide Mentor – Feste
As a "licensed Fool," Feste is literally licensed to criticize and mock the people around him without getting into…