* A brawl erupts: Tybalt, Juliet's cousin, is angered by Romeo's presence at the Capulet feast and challenges him to a duel. Romeo, having recently married Juliet, refuses to fight, hoping to end the feud.
* Mercutio steps in: Furious with Tybalt's insults and Romeo's passivity, Mercutio challenges Tybalt himself. They fight, and Mercutio is wounded.
* A fatal wound: As Romeo tries to intervene and separate them, Tybalt fatally stabs Mercutio under Romeo's arm.
* Mercutio's death: In his final moments, Mercutio utters the famous line, "A plague o' both your houses!", cursing both the Montagues and the Capulets for their feud. He then dies.
Mercutio's death is a pivotal turning point in the play. It fuels Romeo's anger and despair, leading him to kill Tybalt in revenge, thus escalating the feud and setting the stage for the play's tragic conclusion.