ACT I
Macbeth and Banquo, leaders of the Scottish army, meet a group of witches who prophesy the future. They address Macbeth as Thane of Cawdor and King of Scotland, and tell Banquo that he will be the father of kings. The two men try to learn more, but the witches vanish. Messengers arrive with news that Duncan, the current king of Scotland, has made Macbeth Thane of Cawdor. The first part of the witches’ prediction has come true.
In Macbeth’s castle, Lady Macbeth reads a letter from her husband telling her of the events that have just transpired. She resolves to follow her ambitions. A servant announces that Duncan will soon arrive at the castle, and when Macbeth enters, she tells him that they must kill the king. Duncan arrives. Macbeth has a vision of a dagger, then leaves to commit the murder. On his return, he tells his wife how the act has frightened him, and she tells him that he needs more courage. They both leave as Banquo enters with Macduff, a nobleman, who discovers the murder. Macbeth and Lady Macbeth pretend to be horrified and join the others in condemning the murder.
ACT II
Macbeth has become king. Duncan’s son, Malcolm, is suspected of having killed his father and has fled to England. Worried about the prophecy that Banquo’s children will rule, Macbeth and his wife now plan to kill him and his son, Fleance, as well. As Macbeth leaves to prepare the double murder, Lady Macbeth hopes that it will finally make the throne secure.
Outside the castle, assassins wait for Banquo, who appears with his son, warning him of strange forebodings. Banquo is killed, but Fleance escapes.
Lady Macbeth welcomes the court to the banquet hall and sings a drinking song, while Macbeth receives news that Banquo is dead and his son has escaped. About to take Banquo’s seat at the table, Macbeth has a terrifying vision of the dead man accusing him. His wife is unable to calm her unsettled husband, and the courtiers wonder about the king’s strange behavior. Macduff vows to leave the country, which is now ruled by criminals.
ACT III
The witches gather again, and Macbeth visits them, demanding more prophecies. Apparitions warn him to beware of Macduff and assure him that “no man of woman born” can harm him, and that he will be invincible until Birnam Wood marches on his castle. In another vision, he sees a procession of future kings, followed by Banquo. Horrified, Macbeth collapses. The witches disappear and his wife finds him. They resolve to kill Macduff and his family.
ACT IV
On the Scottish border, Macduff has joined the refugees. His wife and children have been killed. Malcolm appears with British troops and leads them to invade Scotland.
Lady Macbeth is sleepwalking, haunted by the horrors of what she and her husband have done.
Macbeth awaits the arrival of his enemies and realizes that he will never live to a peaceful old age. Messengers bring news that Lady Macbeth has died, and that Birnam Wood appears to be moving. English soldiers appear, camouflaged with its branches. Macduff confronts Macbeth and tells him that he was not born naturally but had a Caesarean birth. He kills Macbeth and proclaims Malcolm king of Scotland.
Place: Scotland
Time: 11th century
Act 1
Scene 1: A heath
Groups of witches gather in a wood beside a battlefield, exchanging stories of the "evils" they have done. The victorious generals Macbeth and Banco enter. The witches hail Macbeth as Thane of Glamis (a title he already holds by inheritance), Thane of Cawdor, and king "hereafter." Banco is greeted as "lesser than Macbeth, but greater", never a king himself, but the progenitor of a line of future kings. The witches vanish, and messengers from the king appear naming Macbeth Thane of Cawdor. Macbeth protests that the holder of that title is still alive, but the messengers reply that the former Thane has been executed as a traitor. Banco, mistrusting the witches, is horrified to find that they have spoken the truth. In a duet, Macbeth and Banco muse that the first of the witches' prophecies has been fulfilled. Macbeth ponders how close he is to the throne, and whether fate will crown him without his taking action, yet dreams of blood and treachery: while Banco ponders on whether the minions of Hell will sometimes reveal an honest truth in order to lead one to future damnation.
Scene 2: Macbeth's castle
Lady Macbeth reads a letter from her husband telling of the encounter with the witches. She is determined to propel Macbeth to the throne - by fair means or foul.
Lady Macbeth is advised that King Duncan will stay in the castle that night; she is determined to see him killed (Or tutti, sorgete / "Arise now, all you ministers of hell"). When Macbeth returns she urges him to take the opportunity to kill the King. The King and the nobles arrive and Macbeth is emboldened to carry out the murder (Mi si affaccia un pugnal? / "Is this a dagger which I see before me?"), but afterwards is filled with horror. Disgusted at his cowardice, Lady Macbeth completes the crime, incriminating the sleeping guards by smearing them with Duncan's blood and planting on them Macbeth's dagger. Macduff arrives for an appointment with the King, while Banco stands guard, only for Macduff instead to discover the murder. He rouses the castle while Banco also bears witness to the fact of Duncan's murder. The chorus calls on God to avenge the killing (Schiudi, inferno, . . / "Open wide thy gaping maw, O Hell").
Act 2
Scene 1: A room in the castle
Macbeth is now king: Duncan's son Malcolm has fled the country, suspicion having conveniently fallen on him for his father's murder: but Macbeth is still disturbed by the prophecy that Banco, not he, will found a great royal line. To prevent this he tells his wife that he will have both Banco and his son murdered as they come to a banquet.
Scene 2: Outside the castle
A gang of murderers lie in wait. Banco, sensing danger shares his misgivings with his son. (Come dal ciel precipita / "O, how the darkness falls from heaven"). The murderers attack and stab him to death, but his son escapes.
Scene 3: A dining hall in the castle
Macbeth receives the guests and Lady Macbeth sings a brindisi (Si colmi il calice / "Fill up the cup"). The assassination is reported to Macbeth, but when he returns to the table the ghost of Banco is sitting in his place. Macbeth raves at the ghost and the horrified guests believe he has gone mad. Lady Macbeth manages to calm the situation once - and even mocks it by calling for a toast to the absent Banco (whose death is not yet public knowledge), only for the ghost to appear a second time and terrify Macbeth into insanity again. Macduff resolves to leave the country, saying it is ruled by a cursed hand and only the wicked may remain: the other guests are terrified by Macbeth's talk of ghosts, phantoms and witches. The banquet ends abruptly with their hurried, frightened departure.
Act 3
The witches' cave
The witches gather around a cauldron in a dark cave. Macbeth enters and they conjure up three apparitions for him. The first advises him to beware of Macduff. The second tells him that he cannot be harmed by a man 'born of woman'. The third that he cannot be conquered till Birnam Wood marches against him. (Macbeth: O lieto augurio / "O, happy augury! No wood has ever moved by magic power")
Macbeth is then shown the ghost of Banco and his descendants, eight future Kings of Scotland, verifying the original prophecy. (Macbeth: Fuggi regal fantasima / "Begone, royal phantom that reminds me of Banco"). He collapses, but regains consciousness in the castle.
The act ends with Macbeth recovering and resolving to assert his authority: Vada in fiamme, e in polve cada / "Macduff's lofty stronghold shall / Be set fire....".
Act 4
Scene 1: Near the border between England and Scotland
Scottish refugees stand near the English border (Chorus: Patria oppressa / "Down-trodden country"):
While each version uses the same libretto, the music of this chorus is different. It begins with a less ominous, much shorter orchestral introduction and is sung straight through by the entire chorus.
In the distance lies Birnam Wood. Macduff is determined to avenge the deaths of his wife and children at the hands of the tyrant (Ah, la paterna mano / "Ah, the paternal hand"). He is joined by Malcolm, the son of King Duncan, and the English army. Malcolm orders each soldier to cut a branch from a tree in Birnam Wood and carry it as they attack Macbeth's army. They are determined to liberate Scotland from tyranny (Chorus: La patria tradita / "Our country betrayed").
Scene 2: Macbeth's castle
A doctor and a servant observe the Queen as she walks in her sleep, wringing her hands and attempting to clean them of blood (Una macchia è qui tuttora! / "Yet here's a spot"). She raves about the deaths of both Duncan and Banco, and even about the deaths of Macduff's family, and that all the perfumes of Arabia would not clean the blood off her hands: all are things that the horrified witnesses would never dare to repeat to any living man.
Scene 3: The battlefield
Macbeth has learned that an army of Scottish rebels backed by England is advancing against him, but is reassured by remembering the words of the apparitions, that no man born of woman can harm him. However, in an aria (Pietà, rispetto, amore / "Compassion, honour, love") he contemplates the fact that he is already hated and feared: there will be no compassion, honour and love for him in his old age even if he wins this battle, nor kind words on a royal tomb, only curses and hatred. He receives the news of the Queen's death with indifference. Rallying his troops he learns that Birnam Wood has indeed come to his castle. Battle is joined.
Macduff pursues and fights Macbeth who falls. He tells Macbeth that he was not "born of woman" but "ripped" from his mother's womb. Fighting continues. Mortally wounded, Macbeth, in a final aria - Mal per me che m'affidai / "Trusting in the prophecies of Hell" - proclaims that trusting in these prophecies has caused his downfall. He dies on stage, while Macduff's men proclaim Malcolm to be the new King.