<P> In England, Macduff is informed by Ross that his "castle is surprised; wife and babes / Savagely slaughter'd" (IV. iii. 204--05). When this news of his family's execution reaches him, Macduff is stricken with grief and vows revenge . Prince Malcolm, Duncan's son, has succeeded in raising an army in England, and Macduff joins him as he rides to Scotland to challenge Macbeth's forces . The invasion has the support of the Scottish nobles, who are appalled and frightened by Macbeth's tyrannical and murderous behaviour . Malcolm leads an army, along with Macduff and Englishmen Siward (the Elder), the Earl of Northumberland, against Dunsinane Castle . While encamped in Birnam Wood, the soldiers are ordered to cut down and carry tree limbs to camouflage their numbers . </P> <P> Before Macbeth's opponents arrive, he receives news that Lady Macbeth has killed herself, causing him to sink into a deep and pessimistic despair and deliver his "Tomorrow, and tomorrow, and tomorrow" soliloquy (V.v. 17--28). Though he reflects on the brevity and meaninglessness of life, he nevertheless awaits the English and fortifies Dunsinane . He is certain that the witches' prophecies guarantee his invincibility, but is struck with fear when he learns that the English army is advancing on Dunsinane shielded with boughs cut from Birnam Wood, in apparent fulfillment of one of the prophecies . </P> <P> A battle culminates in Macduff's confrontation with Macbeth, who kills Young Siward in combat . The English forces overwhelm his army and castle . Macbeth boasts that he has no reason to fear Macduff, for he cannot be killed by any man born of woman . Macduff declares that he was "from his mother's womb / Untimely ripp'd" (V. 8.15--16), (i.e., born by Caesarean section) and is not "of woman born" (an example of a literary quibble), fulfilling the second prophecy . Macbeth realises too late that he has misinterpreted the witches' words . Though he realises that he is doomed, he continues to fight . Macduff kills and beheads him, thus fulfilling the remaining prophecy . </P> <P> Macduff carries Macbeth's head onstage and Malcolm discusses how order has been restored . His last reference to Lady Macbeth, however, reveals "' tis thought, by self and violent hands / Took off her life" (V. ix. 71--72), but the method of her suicide is undisclosed . Malcolm, now the King of Scotland, declares his benevolent intentions for the country and invites all to see him crowned at Scone . </P>

Who killed macbeth in william shakespeare's play