Macbeth and Banquo, generals in the service of King Duncan of Scotland, are returning victorious from battle when they are hailed by three witches who predict that Macbeth will become Thane of Cawdor and then King of Scotland, whereas Banquo's descendants will be kings.
The first part of the prophesy is soon fulfilled when Duncan rewards Macbeth's loyal service. Encouraged by this, and playing on her husband's ambition, Lady Macbeth persuades him to murder Duncan while he is a guest at their castle. Malcolm and Donalbain, Duncan's sons, flee to England for safety. Macbeth, now king, has Banquo murdered in an attempt to secure his own position, but Banquo's ghost appears to him at a banquet.
Macbeth visits the witches again. They warn him to beware of Macduff, a noble who has also fled to England, but assure him that he cannot be harmed by any man born of woman. Macbeth orders the murder of Macduff's wife and children.
In England, Malcolm tests Macduff's loyalty and they then raise an army to march against Macbeth. However Macbeth, armed with the witches' prophecy, believes that he is invincible.
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As his enemies draw nearer, Macbeth learns that his wife has killed herself. He faces Macduff in combat but when he learns Macduff was born by Caesarian section, he realises that he must face death.
With Macbeth dead, Malcolm is crowned King of Scotland.