Tybalt enters the scene as Mercutio and Benvolio still quarrel Tybalt is looking for Romeo. Benvolio exclaims "By my head, here come the Capulets" and Mercutio responds, "By my heel, I care not". Benvolio is alarmed, but Mercutio is tough; his "by my heel" remark means that if he comes for a fight then Mercutio will win. Approaching Mercutio and Benvolio, Tybalt tells his followers to stay close to him, as though he feels the need for back-up in case there's trouble, but his words are polite: "Gentlemen, good den: a word with one of you". In no mood for politeness, Mercutio answers, "And but one word with one of us? Couple it with something; make it a word and a blow". Mercutio’s mood towards Tybalt can be seen because of the discussion had between Mercutio and Benvolio in Act 2 Scene 4. Where they talk of how Tybalt just throws around a lot of fancy French phrases, but all he really is, is a French disease. Mercutio and Tybalt draw swords as Mercutio says it's the fiddlestick to whose music Tybalt will dance. Dramatic effect is used here because the audience know that a fight is most certainly going to break out.
As soon as Romeo turns up Tybalt looses all interest in Mercutio saying "Well, peace be with you, sir: here comes my man". At this Mercutio is insulted on behalf or Romeo, it is as if Tybalt is referring to Romeo as his servant “man” so Mercutio says that the only way Romeo will “follow” you is into battle. Tybalt ignores Mercutio and confronts Romeo saying "Romeo, the love I bear thee can afford No better term than this: thou art a villain" but Romeo does not act at all like expected on the contrary. He answers, "Tybalt, the reason that I have to love thee Doth much excuse the appertaining rage to such a greeting" Romeo is saying that he has a reason to love Tybalt and therefore he's going to overlook the insult. The reason being he is now secretly related to him through marriage to Juliet. Romeo the says that he is not a villain and starts to leave but Tybalt, dumbfounded at Romeos talk of love to Tybalt tries again to start a fight "Boy, this shall not excuse the injuries / That thou hast done me; therefore turn and draw". At this Romeo does turn but does not draw, instead he gives more loving words "I do protest I never injured thee, But love thee better than thou canst devise, Till thou shalt know the reason of my love". He ads that he loves the name Capulet as much as his own (Juliet) and asks Tybalt to be satisfied with that.
We know that Mercutio wanted to fight Tybalt before and he now feels that the reason Romeo will not fight is because he is intimidated by Tybalt so he decides to take up the matter saying "Tybalt, you rat-catcher, will you walk?" rat catcher because Tybalt is known as the king of cats and will you walk meaning can we go somewhere to settle this. Tybalt replies "What wouldst thou have with me?" but Mercutio’s intention is clear. However Tybalt does not seem to keen to fight Mercutio and says "Will you pluck your sword out of his pilcher by the ears? make haste, lest mine be about your ears ere it be out" meaning that if something has to be pulled by its ears to come out it does not really want to come out meaning Tybalt’s sword and implying he does not really want to fight. Again here the dramatic effect is that Mercutio wants to fight Tybalt, but Tybalt wants to fight Romeo. So the audience can see that now there is no alternative to fighting to settle the dispute.
They begin to fight seeing a moment Romeo steps forward to stop the fight and as he stands between Tybalt and Mercutio Tybalt lunges his sword under Romeo’s arm and into Mercutio’s heart. At this Tybalt promptly panics and runs. With the stab wound in his heart Mercutio seems to know of his impending death and takes quite a light mood towards it say that his wound is “Not as deep as a well nor wide as a church door but it is enough” and says that “if you look for me tomorrow you will find me a grave man” implying he will be in his grave by tomorrow. Then sensing his imminent death he shouts “a plague o’both your houses!” We can hear that the dying Mercutio feels cheated neither the house of Montague or Capulet is worth dying for, and Tybalt has got away without a scratch. Mercutio’s curse here is significant because later in the play we know that both houses loose a member and it is as if this curse has come true.
As Mercutio lies dead Romeo says, "This day's black fate on more days doth depend; this but begins the woe, others must end" Romeo now knows that he will go and fight Tybalt to avenge Mercutio’s death but it will not be the end of anything. As Romeo catches up with Tybalt he says "Either thou, or I, or both, must go with him" meaning that he will fight to the death knowing that Mercutio’s soul is just above their heads. Here Romeo’s passion to kill Tybalt overcomes Tybalt’s technique and Tybalt is slain. As Romeo stands in a daze of what he has just done Benvolio informs him that "Stand not amazed: the prince will doom thee death, If thou art taken: hence, be gone, away!" meaning that Romeo had better leave before word of this brawl in the streets meets the Prince. At this Romeo cries "O, I am fortune's fool!" and then runs. Here you can see that this will now affect the outcome of the play because now if Romeo stays he will be killed but if leaves he must leave his beloved Juliet. When Romeo refers to him being fortunes fool he is meaning that everything that has happened could not be controlled by him and is as if he has been played by fate.
In Verona bodies of Tybalt and Mercutio now lie before the Prince, The prince asks what happened to trusted Benvolio and he tells of the bloody affray al though meet with some objection from Lady Montague. "And for that offence immediately we do exile him hence" says the Prince as Romeo is banished from Verona.
Act 3 Scene 1 was a pivotal point in the play, many scenes led up to it and from it. As you can imagine if the events from this scene had been different then the outcome of the play would have been considerably changed. For example if the Prince had ordered Romeo to Death then its quite probable that Juliet would still be alive. However the scenes leading up to it could not have averted what happened like the letter from Tybalt to Romeo or the talk between Mercutio and Benvolio about Tybalt. There has also been a lot of dramatic effect in the scene and there has been a lot of talk and threatening that has led up to an inevitable point that has changed the play and influenced the whole outcome of it. So therefore I conclude that this was the most significant Scene and Act in the play.