Three witches assemble on a heath for an encounter with Macbeth. Returning from victory on the battlefield Macbeth and Banquo meet these “weird sisters,” who prophesy that Macbeth will become king and that Banquo's heirs will reign thereafter. Soon after, Macbeth receives word that he has been made Thane (clan chief) of Cawdor, which leads him to give credence to the witches' foresight. He shares his news with his wife, and she begins to plot to murder King Duncan so that Macbeth can become king. News arrives that Duncan will visit the Macbeths' castle, and Lady Macbeth persuades her husband to kill him that night. She lays plans to drug the king's guards, so that Macbeth may slip into the king's chamber. As he makes his way there Macbeth sees a vision of a floating dagger signaling the way. Having murdered the king, Macbeth returns to his wife with the bloody daggers still in his hands. Terrified that the murder has woken other sleepers, Macbeth begins to panic until his wife calms him. As the couple leaves to wash themselves Page 269  |  Top of Articleof the king's blood, a knocking is heard at the gate. The porter ushers in Macduff, who finds the king's body and raises the alarm. Macbeth murders the guards in case they wake. On hearing of their father's murder, the king's sons, Malcolm and Donalbain, leave for England.

Macbeth becomes king, although Banquo harbors secret fears that he murdered King Duncan. Fearing Banquo's suspicions, Macbeth arranges his murder, but Banquo's son Fleance escapes the killers. Macbeth is terrified when Banquo's ghost appears at a banquet he holds that evening. Lady Macbeth tries to distract their dinner guests from her husband's strange behavior, especially when he addresses an empty chair.

Macbeth returns to find the witches and is told that his throne is secure until Birnam Wood marches toward Dunsinane. He feels further reassured when told that he cannot be killed by anyone born of woman. On hearing that Macduff has traveled to England to persuade Malcolm to lead a rebel army, Macbeth orders the murder of Macduff's wife and children. This terrible news reaches Macduff in England and strengthens his resolve to be revenged.

Lady Macbeth's guilt for Duncan's death leaks out when she is heard speaking of the murder in her sleep. While Macbeth believes that he can see a forest walking toward his castle, he hears that his wife has died. The moving wood is in fact an army carrying the branches of trees. In the battle that ensues, Macduff reveals that he was ripped from his mother's womb; the prophecy is complete, and Macbeth is killed.

The Macbeths risk everything to become king and queen of Scotland. In murdering King Duncan they are committing the greatest of sins: regicide. The couple is fully aware that their desire for the crown is criminal and diabolical, and yet they resolve upon this course of action that will bring calamity to them both. Like Richard III, the Macbeths discover to their despair that gaining the throne will not bring them contentment. Macbeth is convinced that he will only rest easy once he knows that he is safely in power: “To be thus is nothing / But to be safely thus” (3.1.49–50). To be “safely thus” would mean that there are no contenders for the throne left alive. The Macbeths find themselves trapped in a cycle of violence, haunted by their deed and the “horrible imaginings” (1.3.137) that ensue: “Blood will have blood” (3.4.121). The killing must continue.

Macbeth is literally and symbolically a dark play. About two-thirds of it takes place at night, lending the drama an eerie intensity. Ghosts walk at night; deadly deeds are committed under the cover of darkness; and nighttime brings nightmares for those with a guilty conscience. The audience's relationship with Macbeth also darkens scene by scene as he falls from being a trusted warrior to becoming a Machiavellian murderer.

Traces of humanity are gradually stamped out as the drama progresses. Lady Macbeth calls upon “spirits / That tend on mortal thoughts” (1.5.39–40) to “unsex” her, filling her with “direst cruelty” (1.5.42). In order to fulfill her murderous ambition, she must in effect transform herself into a merciless monster. Shakespeare draws attention to her womanliness in order to emphasize her fierce rejection of her own femininity. Fearing that her husband is “too full o'th' milk of human kindness” (1.5.16), she encourages him to harden his heart and place ambition above consideration for others: “I have given suck, and know / How tender 'tis to love the babe that milks me. / I would, while it was smiling in my face, / Have plucked my nipple from his boneless gums / And dashed the brains out, had I so sworn / As you have done to this” (1.7.54–59).

As the couple settle upon their homicidal plan, their dependency upon one another strengthens, but so, too, does their sense of entrapment and claustrophobia. The couple share a murderous secret that simply cannot be disclosed. The secret ultimately devours them both and serves to put distance between them.

Macbeth does not enter blindly into the murder of Duncan, although he does show some unwillingness to commit. Shakespeare complicates our relationship with Macbeth by voicing the character's reluctance to go through with the crime. Having listened to his wife's reaction to the witches' prophecy that he “shalt be king hereafter” (1.3.48), he states firmly that “We will proceed no further in this business” (1.7.31). For a moment it looks as though Macbeth will resist temptation and conquer his “Vaulting ambition” (1.7.27). His wife's stinging taunts, however, make him think again. Lady Macbeth launches into a targeted emotional assault that offends, humiliates, and shocks her husband in equal measure:

“Was the hope drunk / Wherein you dressed yourself? Hath it slept since? / And wakes it now to look so green and pale / At what it did so freely? From this time / Such I account thy love. Art thou afeard / To be the same in thine own act and valour / As thou art in desire? Wouldst thou have that / Which thou esteem'st the ornament of life, / And live a coward in thine own esteem, / Letting ‘I dare not’ wait upon ‘I would,’ / Like the poor cat i'th' adage?” (1.7.35–44).

In the space of just 10 lines, Lady Macbeth questions her husband's masculinity, honor, ambition, courage, and love for her. Macbeth's male pride overpowers his questioning mind, resulting in the defensive riposte “I dare do all that may become a man” (1.7.46). How much did Macbeth actually want the crown for himself, and to what extent does he carry out his part in the murder to confirm and maintain his understanding of his own manhood? Typically, Shakespeare does not settle upon a straightforward answer. The audience's responses to Macbeth's actions are further complicated by the role played by the witches throughout the drama. Did Macbeth have a choice? Was his fate always to murder Duncan and become king himself?

Macbeth's “heat-oppressèd brain” (2.1.39) comes to haunt him as much as the witches' prophecies. Paranoia practically paralyzes Macbeth, and his imagination proves a constant torment. As he prepares to murder Duncan, he sees a floating dagger sign-posting his way to the king's bedchamber.

Has this dagger been conjured by the weird sisters? Or is it merely, as Macbeth suspects, a “dagger of the mind” engendered through fear and his reluctance to act upon his ambitions? His imagination will not be suppressed. Having murdered the king, Macbeth imagines that he will never sleep again:

“Methought I heard a voice cry ‘Sleep no more, / Macbeth does murder sleep’—the innocent sleep, / Sleep that knits up the ravelled sleave of care, / The death of each day's life, sore labour's bath, / Balm of hurt minds, great nature's second course, / Chief nourisher in life's feast” (2.2.33–38).

The desire to unburden one's self of problems by telling others is all too human. Shakespeare skillfully depicts the breakdown of a marriage under stress, which leaves Lady Macbeth vulnerable psychologically. Lacking her husband's attention, she ruinously divests herself of her troubles while speaking in her sleep: “Out, damned spot; out, I say. One, two,—why, then 'tis time to do't. Hell is murky. Fie, my lord, fie, a soldier and afeard? What need we fear who knows it when none can call our power to account? Yet who would have thought the old man to have had so much blood in him?” (5.1.33–38).

As the Doctor diagnoses, “infected minds / To their deaf pillows will discharge their secrets” (5.1.69–70). Lady Macbeth's disclosure puts her own life and her husband's at risk. Shakespeare draws a stark contrast between his initial portrait of Lady Macbeth and her final depiction. While she was once strong and controlling, she becomes a pitiful shadow of her former self. Her deadly secret has drained the life from her, and she is left to obsess about death. Her own will follow soon enough.

At moments of extreme crisis or violence, Shakespeare has Macbeth voice some of the playwright's most poetic reflections upon the nature of existence itself. The murder of Duncan prompts thoughts on the soothing qualities of sleep, while Lady Macbeth's death encourages a meditation upon the transitory nature of life: “Out, out, brief candle. / Life's but a walking shadow, a poor player / That struts and frets his hour upon the stage, / And then is heard no more. It is a tale / Told by an idiot, full of sound and fury, / Signifying nothing” (5.5.22–27).

Having killed the king, Macbeth faces a future of “restless ecstasy” (3.2.24). His mind is “full of scorpions” (3.2.37) and his every thought is about the fact that he has “scorched the snake, not killed it” (3.2.15). While Banquo lives, Macbeth fears exposure. He is also angered by the witches' prophecy that Banquo's sons will reign after him. Banquo certainly suspects Macbeth of villainy:

The witches become a chorus in Guiseppe Verdi's opera Macbeth. Here, the San Francisco Opera company performs a production in modern dress in 2007.

“Thou hast it now: King, Cawdor, Glamis, all / As the weird women promised; and I fear / Thou played'st most foully for't.” (3.1.1–3).Macbeth's decision to have his friend murdered is taken alone; he is keen that his wife “Be innocent of the knowledge” (3.2.46). Banquo's murder creates a rift between husband and wife, and as a result produces one of the play's most thrilling moments: the appearance of Banquo's ghost.

As Macbeth attempts to join his guests at the banquet table, he cannot see a chair reserved for himself. Although his guests motion toward an empty seat, the king recoils in horror and begins to address Banquo's ghostly figure, visible only to himself: “Never shake / Thy gory locks at me” (3.4.49–50). The king's behavior is sufficiently alarming that it prompts his wife to placate the bewildered and discomfited diners: “The fit is momentary. Upon a thought / He will again be well. If much you note him / You shall offend him, and extend his passion. / Feed, and regard him not” (3.4.52–57).

In performance this moment can be played to emphasize the black humor. If the king's “fit” is particularly dramatic then it can prove impossible for the diners to “regard him not.” As the king's reactions to the ghost grow more extreme, Lady Macbeth's need to take control of the situation becomes pressing. She takes her husband aside and tries to reason with him, Macbeth's mind is, obsessed with thoughts of blood: “Blood hath been shed ere now, i'th' olden time, / Ere human statute purged the gentle weal; / Ay, and since, too, murders have been performed / Too terrible for the ear. The time has been / That, when the brains were out, the man would die, / And there an end. But now they rise again / With twenty mortal murders on their crowns, / And push us from our stools. This is more strange / Than such a murder is” (3.4.74–82).

Shakespeare is retracing here the dynamic between the Macbeths that he created just after the murder of Duncan. Having killed the king, Macbeth froze with bloody daggers in hand as a wave of nervous thoughts swamped his mind. Fortunately for the Macbeths they were in private, and Lady Macbeth had been able to shake her husband from his terrifying thoughts.

Macbeth's strange behavior at the banquet is played out in front of the puzzled guests. When the ghost appears before him for a second time, he cannot contain his horror: “It will have blood, they say. Blood will have blood. / Stones have been known to move, and trees to speak, / Augurs and understood relations have / By maggot-pies and choughs and rooks brought forth / The secret'st man of blood” (3.4.121–125).

By the play's close Macbeth's world has come crashing down, and he finds little left in life to delight him: “I have lived long enough” (5.3.24). The witches' improbable prophecies all come to fruition, and Macbeth leaves the stage fighting despite the odds being against him:

“Though Birnam Wood be come to Dunsinane, / And thou opposed being of no woman born, / Yet I will try the last “(5.10.30–32).

It is only through the deaths of this “dread butcher and his fiend-like queen” (5.11.35) that the blood-letting can be brought to a close. “The time is free” (5.11.21), says Macduff, and he hails the new king Malcolm, who can build a future for Scotland, free from tyranny.