1.4: On their way to crashing the Capulet party, Mercutio mocks his best friend Romeo for being infatuated with Rosaline. Then he starts riffing on Queen Mab, a strange fairy who visits people in their dreams. Romeo and Benvolio finally drag him off to the party.
1.5: Mercutio attends the Capulet bash, but has no lines.
2.1: Mercutio and Benvolio can't find Romeo after the party. Mercutio tries to conjure Romeo by saying dirty things about Rosaline, the girl Romeo was infatuated with. The attempt fails, so Mercutio heads home.
2.4: Mercutio and Benvolio still haven't figured out where Romeo disappeared to the night before. They discuss Tybalt, who has sent a letter to Romeo's house challenging him to a duel. Mercutio mocks Tybalt and calls him the "prince of cats." When Romeo finally shows up, Mercutio is glad to see he's moved on from Rosaline. Juliet's nurse marches in and demands to speak with Romeo. Mercutio teases her with inappropriate jokes and pretends to flirt with her.
3.1: Mercutio is chilling with Benvolio when Tybalt shows up looking for Romeo. Mercutio and Tybalt trade insults. Romeo appears, but he refuses to fight with Tybalt, even when Tybalt provokes him. Furious at his best friend's cowardice, Mercutio challenges Tybalt to a duel. He and Tybalt fight. When Romeo tries to stop them from dueling, Tybalt wounds Mercutio. Although he jokes about his wound, Mercutio is seriously hurt.
3.1: Mercutio dies cursing the Montagues and Capulets for dragging him into their quarrel. "A plague o'both your houses – they have made worm's meat of me," he says.