The plot of this story revolves around anger. The family feud existing between the Capulet's and the Montegues symbolizes misplaced anger that has transcended time and left the characters missing the purpose behind it. The families simply hate one another for no reason.
This anger comes to a head when Tybalt dies at Romeo's sword. What might have been two teenage boys quarreling and showing off has turned into a fatal brawl, giving more fuel to the fire of the families' hatred of one another.
Romeo and Juliet must then defy their parents to be together, running away, and then ultimately killing themselves- each thinking the other dead. ironically, it takes the sacrifice of these two young teens to make their families see how poisonous the anger has been. The message then is to put anger aside before it costs someone his or her life.