In Macbeth, Macbeth and Lady Macbeth conspire to murder Duncan so that they can satisfy their "vaulting ambition," (I.vii.27). Macbeth is so influenced by the prophesies of the witches who have assured him that he "shalt be King hereafter," (I.iii.50), that he is both excited and disgusted by his own, as he calls it, "earnest of success,"(132). Macbeth's determination wanes, however, and it is up to Lady Macbeth to persuade him; which she does by suggesting that, if he does not murder Duncan and further his own aims, then he is a "coward in thine own esteem," (I.vii.43), and is less of a man for it. Lady Macbeth goes on to explain to Macbeth how they will kill Duncan and blame "his spongy officers," (71) for the murder which Lady Macbeth calls "our great quell," (71). She is confident that, by using the guards' own daggers, the guards will be found guilty. Macbeth is also sufficiently persuaded.
Having prepared everything for Macbeth and remarking that she would have killed Duncan herself, "had he not resembled my father," (II.ii.12), Lady Macbeth is shocked at Macbeth's apparent confusion after killing Duncan, especially as he has brought the daggers with him and so threatens their plan to blame, "the sleepy grooms," (49) and she has to return them herself and hope that their plan has not been compromised.
Macduff comes to wake Duncan and after a brief exchange with Macbeth, he goes to wake Duncan. Macbeth, trying to remain normal, chats with Lennox who remarks how the wind, during the "rough" night, has caused chimneys to blow down and even how there were strange "lamentings," and even "screams of death," (II.iii.54) that made it a terrible night. When Macduff returns to Macbeth and Lennox, he can barely contain his horror at having seen Duncan dead and "the life of the building" (67) apparently "stole(n)." Having discovered the body, Macduff wants to awaken the others and even tries to, ironically, protect "gentle" Lady Macbeth from the horror. Macbeth then tries to cover his tracks by admitting to having killed the guards but, he claims, he did so when he saw what they had done to Duncan. There are concerns about "treasonous malice," (131), and Macbeth will continue scheming in an effort to ensure his place as king, at any cost.
Macduff discovers King Duncan's body. He is led by Lennox to where King Duncan had slept. Once he arrives there, he is grieved at the sight of King Duncan's murder. He exclaims that King Duncan's life has been stolen. Then he yells for the others to awake:
Awake, awake! Ring the alarms bell. Murder and treason!
Banquo and Donalbain! Malcolm! Awake!
Shake off this soft sleep, death's disguise,
And look on death itself! Go up, go up, and see
The great destruction's image! Malcolm! Banquo!
Rise up as you would from your graves, and walk like spirits
To see this horror!
Then lady Macbeth stirs. She pretends to be offended by being awakened:
That such a hideous trumpet calls to summon
The sleepers of the house? Speak, speak!
Macduff does not desire to tell her what she already knows. Ironically, he refers to her as a gentle lady, claiming that the news will kill her:
O gentle lady,
It is not for you to hear what I can speak.
The repetition, in a woman's ear,
Would murder you as you heard it.
Then Macduff yells for Banquo, exclaiming King Duncan has been murdered:
O Banquo, Banquo!
Our royal master's murdered!