In the beginning Macbeth was such a nice guy. That changed after he met the three witches. When Macbeth first meets the witches they say two things that cause Macbeth to be evil. These two predictions told by the witches caused the changes that happened within Macbeth. When Lady Macbeth finds out about the predictions, she drives Macbeth even harder. Lady Macbeth tries to get Macbeth to kill Duncan, because she wants Macbeth to be king. After Macbeth killed Duncan he killed the King's guards, so no one could question them. This was just the start of Macbeth's transition into evil.
Later in the play Banquo starts to have a bad feeling about Macbeth. Macbeth realizes this about Banquo and he starts to have feelings about killing Banquo. This is not the only reason he feels this way, the witches had also made predictions for Banquo. Macbeth does not want any of Banquo's family to rule Scotland, so Macbeth hires two murderers to kill Banquo and his son Fleance. The murderers end up killing Banquo, but Fleance gets away. This was one big step Macbeth took on his way to becoming evil.
Macbeth is progressively becoming more evil. The next step is killing Macduff. Macduff had a feeling that Macbeth was the one who killed Duncan. Macbeth was also considering killing Macduff because he went to England to get Malcolm to come back and rule Scotland. Macbeth decided to send a murderer to Macduff's house to kill his family. This would show Macduff that he had better watch out, and it would scare Macduff. This was the final step to becoming evil.
In William Shakespeare's play, Macbeth, the main character goes through a drastic change. Throughout the playchanging from good to evil. The evil trail ends when Macbeth is killed by Macduff, and...