Critic Harold Bloom writes that no other play by Shakespeare "so engulfs us in phantasmagoria as Macbeth." From beginning to end, the preternatural and blood dominate.
The intrusion of the supernatural into the first scene stirs the blood-ridden warrior with desires for power as Macbeth is greeted by the witches as Thane of Glamis, Thane of Cawdor, and King. The idea of his acquiring such powerful positions tempts Macbeth, but Banquo warns him against the trap of the "instruments of darkness." Nevertheless, the bewildered Macbeth who realizes "nothing is/But what is not," is tempted:
If chance will have me King, why, chance may crown me
Without my stir. (1.3.155)
However, once the treacherous Thane of Cawdor is executed and Macbeth is made Thane, he no longer doubts the witches' predictions. However, by his entertainlng the preternatural, Macbeth risks disturbing the Chain of Being and he risks conflict with Banquo, who is aware of the predictions and has cautioned him against believing them.
Although Macbeth is made Thane of Cawdor as predicted, he has trouble believing that he can be king because Duncan has named his eldest son Malcolm heir to his throne, declaring him Prince of Cumberland. Now, the cupidous Macbeth finds Malcolm an impediment to his advancement,
The Prince of Cumberland! That is a step
On which I must fall down, or else o'erleap,
For in my way it lies. (1.4.55-58)
With the entry of Lady Macbeth into this act, new conflicts enter Macbeth's life as his wife, who thinks he possesses too much of the "milk of human kindness" to assassinate King Duncan, pushes her plan upon her husband, who would rather wait some. And, as she has foretold, Macbeth does lack resolve, but his "vaulting ambition" prods him.
When Banquo arrives at Inverness, he wishes to have the discussion about the witches to which they have agreed; however, Macbeth tells him it is not the time. Banquo agrees, but Macbeth wants him to side with him when the time comes, telling Banquo "It shall make honor for you" (2.1.26).
Macbeth is trouble by his thoughts of murdering the king, imagining a dagger before him and Nature out of order. Lady Macbeth, who has declared herself the stronger, cannot kill Duncan because he looks too much like her father; so, Macbeth commits regicide, but hears condemnations in his mind afterwards. Here the motif of blood is introduced as Macbeth feels that he cannot wash the blood of Duncan from his hands, but, ironically, Lady Macbeth tells him it only takes water.
With the natural order disrupted by the death of the king, odd things happen. And, Macduff, who does not attend the coronation of Macbeth is placed in opposition to Macbeth.
Feeling that Macbeth has had a hand in making the witches' prophesies come to fruition, Banquo worries what may become of himself. But, Macbeth insists on keeping Banquo and his son close to him because they threaten his position, so he invites them to the palace. Further in the act, Macbeth talks to his wife, but he does not reveal his intentions to her of having Banquo and Fleance killed. So, his relationship with his wife has changed.
The hired murderers kill Banquo, but because his son flees, Banquo can still be the father of kings through Fleance. This disturbing thought bothers Macbeth, and when he sees the ghost of Banquo he is horrified. Later, worried why Macduff was not at the feast, Macbeth begins to come undone.