In the beginning of the play, Macbeth and Banquo meet three witches. The witches predict that Macbeth will be Thane of Glamis, Thane of Cawdor, and king. They tell Banquo that his sons will become kings. At that point Macbeth was already Thane of Glamis because of his father. He also had been named Thane of Cawdor, but he hadn't found out yet. This all made him think that maybe someday he could be king, but he didn't know how. At first Macbeth was hesitant about killing Duncan, but Lady Macbeth persuaded him into doing it. Duncan was coming to Macbeth's Castle to spend the night. The plan was to get the guards drunk, kill Duncan in his sleep, and blame it on the guards.
Macbeth made two mistakes in the murder. First, he brought the murder weapons back with him instead of leaving them by the guards. Second, when they asked him why he killed the guards, he rambled on about his anger and his rage. Lady Macbeth had to fake faint to distract their dinner guests from what Macbeth was saying. One thing that went Macbeth's way was that Malcolm and Donalbain fled because they thought that whoever killed their father would come back to kill them next.
Now that Macbeth was king he felt more and more paranoid about what he had done. Macbeth hired murderers to kill Banquo and his son. The murderers killed Banquo, but his son escaped. This meant that the prophecy that Banquo's son would become king could still come true.
Again Macbeth made another big mistake. At the dinner party he kept mentioning that he wished that Banquo was there. Finally Banquo's ghost appears and sits in Macbeth's seat at the table. Macbeth keeps screaming at the ghost until it disappears. Lady Macbeth told the guests that Macbeth was ill and that it would pass. Then Macbeth again says that he wished Banquo was there. When the ghost appears again, Macbeth again screams at it. Lady Macbeth said it would be best if the guests leave because Macbeth was very ill. This shows how Macbeth was losing control and how what he did was haunting him.
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