Don John is a character from William Shakespeare's play, "Much Ado About Nothing." He is the illegitimate brother of Don Pedro and is often portrayed as a brooding and resentful figure. His actions are driven by jealousy and a desire to disrupt the happiness of others, particularly targeting Claudio and Hero. Throughout the play, Don John schemes to create chaos, leading to misunderstandings and conflict. His manipulative nature contrasts with the more lighthearted characters, making him a key antagonist. Ultimately, his plans fail, and he is captured, highlighting the themes of deception and the consequences of malice.