In the Tragedy of Macbeth, from the beginning of Act I to the end of Act III, the major change we see in Macbeth is that he is quick to use treachery to suit his needs.
Macbeth is a Scottish general and the thane of Glamis who is led to wicked thoughts by the prophecies of the three witches, particularly after their prophecy that he will be made thane of Cawdor comes true. Macbeth is a brave soldier and a powerful man, but he is not a virtuous one.