King Duncan’s generals, Macbeth and Banquo, encounter three strange women on a bleak Scottish moorland on their way home from quelling a rebellion. The women prophesy that Macbeth will be given the title of Thane of Cawdor and then become King of Scotland, while Banquo’s heirs shall be kings. The generals want to hear more but the weird sisters disappear. Duncan creates Macbeth Thane of Cawdor in thanks for his success in the recent battles and then proposes to make a brief visit to Macbeth’s castle.
Lady Macbeth receives news from her husband of the prophecy and his new title and she vows to help him become king by any means she can. Macbeth’s return is followed almost at once by Duncan’s arrival. The Macbeths plot together and later that night, while all are sleeping and after his wife has given the guards drugged wine, Macbeth kills the King and his guards. Lady Macbeth leaves the bloody daggers beside the dead king. Macduff arrives and when the murder is discovered Duncan’s sons, Malcolm and Donalbain flee, fearing for their lives, but they are nevertheless blamed for the murder.
Macbeth is elected King of Scotland but is plagued by feelings of guilt and insecurity. He arranges for Banquo and his son, Fleance to be killed, but the boy escapes the murderers. At a celebratory banquet, Macbeth sees the ghost of Banquo and disconcerts the courtiers with his strange manner. Lady Macbeth tries to calm him but is rejected.
Macbeth seeks out the witches and learns from them that he will be safe until Birnam Wood comes to his castle, Dunsinane. They tell him that he need fear no-one born of woman, but also that the Scottish succession will come from Banquo’s son. Macbeth embarks on a reign of terror and many, including Macduff’s family, are murdered, while Macduff himself has gone to join Malcolm at the court of the English king, Edward. Malcolm and Macduff decide to lead an army against Macbeth.
Macbeth feels safe in his remote castle at Dunsinane until he is told that Birnam Wood is moving towards him. The situation is that Malcolm’s army is carrying branches from the forest as camouflage for their assault on the castle. Meanwhile, Lady Macbeth, paralysed with guilt, walks in her sleep and gives away her secrets to a listening doctor. She kills herself as the final battle commences.
Macduff challenges Macbeth who, on learning his adversary is the child of a Caesarian birth, realises he is doomed. Macduff triumphs and brings the head of the traitor to Malcolm who declares peace and is crowned king.