Driven by desperation and increasing mental instability, Macbeth seeks out the witches again for further prophecies. They offer him three new apparitions: to beware Macduff, that no man 'of woman born' can harm him, and that he will not be vanquished until Birnam Wood comes to Dunsinane. These prophecies, while seemingly reassuring, are deliberately ambiguous and contribute to Macbeth's false sense of invincibility.
Upon learning that Macduff has fled to England, Macbeth, in a fit of rage and paranoia, orders the brutal murder of Macduff's wife and children. This act of senseless cruelty marks a significant turning point, demonstrating his complete moral degradation and solidifying his image as a ruthless tyrant. It also provides Macduff with a powerful personal motive for revenge.
In England, Malcolm tests Macduff's loyalty before revealing his true intentions to reclaim the throne. When Macduff receives the devastating news of his family's slaughter, he vows to avenge them and joins forces with Malcolm and the English army. This alliance sets the stage for the final confrontation and the eventual restoration of order in Scotland.
Overwhelmed by guilt and haunted by her crimes, Lady Macbeth descends into madness, sleepwalking and hallucinating bloodstains on her hands, ultimately taking her own life offstage. Her demise underscores the psychological toll of their actions and the inescapable nature of their guilt. This tragic end for Lady Macbeth contrasts sharply with her initial ruthless resolve.
As the English army, led by Malcolm and Macduff, advances towards Dunsinane, they camouflage themselves with branches from Birnam Wood, fulfilling one of the witches' prophecies. Macbeth, despite hearing of his wife's death and the seemingly impossible movement of the wood, remains defiantly convinced of his invincibility due to the 'no man of woman born' prophecy.
In the climactic duel, Macduff confronts Macbeth and reveals that he was 'from his mother's womb untimely ripped' (born by Caesarean section), thus not 'of woman born' in the traditional sense. This revelation shatters Macbeth's last vestige of confidence and fulfills the final prophecy. Macduff ultimately kills Macbeth, bringing an end to his tyrannical reign.
With Macbeth defeated, order is restored to Scotland, and Malcolm, Duncan's rightful heir, is crowned king. The play concludes with the re-establishment of legitimate rule and the promise of a peaceful future, emphasizing the tragic consequences of ambition unchecked by morality and the ultimate triumph of justice over tyranny.