The Third Murderer in Macbeth
There is much speculation as to who the third murderer is who assisted in the slaying of Banquo. Macbeth, Lady Macbeth, and one of the Weird sisters are a few of the best candidates as to filling this role. Each of these three main characters has their own motive as to why they would want to join in on the assassination. Out of these three possibilities of filling this third murderer's role, all have reasons as to why they could or could not fill the position.
At this time in the play, Macbeth is paranoid about Banquo turning against him. In the opening of act three, Macbeth hires two hit men to take out Banquo and his son Fleance. The two men Macbeth hires probably did not match to Banquo's great skill in fighting. This could give Macbeth a reason to want to join the other two murderers in making sure that the plan was carried out. After they murder Banquo, the third murderer says, "Who did strike out the light?" and "there's but one down; the son is fled" (3.3.18). He is the one who realizes that someone turned out the light and that Fleance escapes.
Although there is a possibility that Macbeth could aid in the killing of Banquo, he needs an alibi. Prior to the assassination, Macbeth explains to the two murderers that he has to keep in good relations with the people around him. "And something from the palace (always thought / that I require a clearness), and with him, / to leave no rubs nor botches in the work" (3.1.131-133). He needs to have the murder take place away from his castle. The scene following the murder of Banquo, the two murderers inform Macbeth of Fleance escaping. When Macbeth learns this knowledge, it seems to shock him and surprise him. Macbeth exclaims in response to hearing the news, "Thanks for that! There the grown serpent lies; the worm that's fled hath / nature that in time will venom breed, no teeth for the present" (3.4.30-33).
Lady Macbeth also feels that Banquo was a threat to their rule. She asks, "Is Banquo gone from court?" (3.2.1). Lady...