Act 3 presents a change in the story with important figures assassinated and rebels preparing for war against Macbeth who has become tyrannical “Free from our feasts and banquets bloody knives” (III, VI. 35).
For me Act Three is one of the saddest because it kills off Ban quo, a favored character of mine. Therefore, while not a change I would have liked a sequel of the intro, or at least expansion, detailing the civil war mentioned in Act One.
I believe in Act Three you begin to see how inescapable the witches prophecy is, specifically by the inability of Ban quo’s line from being snuffed out and shaping of a rebellion by outcasts “Hath so exasperated the king that he Prepares for some attempt of war” (III, VI. 37).
Macbeth 