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.
[Revised version, 1865: Vieni! t'affretta!/ "Come! Hurry!"]
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.
[1865 revised version: In her aria, La luce langue / "The light fades", Lady Macbeth exults in the powers of darkness]
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.
[Original 1847 version: 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....".]
A herald announces the arrival of the Queen (Duet: Vi trovo alfin! / "I've found you at last"). Macbeth tells his wife about his encounter with the witches and they resolve to track down and kill Banco's son, as well as Macduff and his family (whom they do not yet know has already fled the country). (Duet: Ora di morte e di vendetta / "Hour of death and of vengeance").
Act 4
Scene 1: Near the border between England and Scotland
Scottish refugees stand near the English border (Chorus: Patria oppressa / "Down-trodden country"):
[Original 1847 version: 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.]
[1865 revised version: the music is divided into sections for the male and female members, then it unites them towards the end. The revised version is 2 minutes longer than the original.]
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.
[Original 1847 version's ending: 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.]
Macduff pursues and fights Macbeth who falls wounded. He tells Macbeth that he was not "born of woman" but "untimely ripped" from his mother's womb. Macbeth responds in anguish (Cielo! / "Heaven") and the two continue fighting, then disappear from view. Macduff returns indicating to his men that he has killed Macbeth. He then turns to Malcolm, hailing him as King. The scene ends with a hymn to victory sung by bards, soldiers, and Scottish women (Salve, o re!/ "Hail, oh King!). Malcolm as King, and Macduff as hero, together swear to restore the realm to greatness.

Place: Paris
Time: Around 1830
Act 1
In the four bohemians' garret (Christmas Eve)
Marcello is painting while Rodolfo gazes out of the window. They complain of the cold. In order to keep warm, they burn the manuscript of Rodolfo's drama. Colline, the philosopher, enters shivering and disgruntled at not having been able to pawn some books. Schaunard, the musician of the group, arrives with food, wine and cigars. He explains the source of his riches: a job with an eccentric English gentleman, who ordered him to play his violin to a parrot until it died. The others hardly listen to his tale as they set up the table to eat and drink. Schaunard interrupts, telling them that they must save the food for the days ahead: tonight they will all celebrate his good fortune by dining at Cafe Momus, and he will pay.
The friends are interrupted by Benoît, the landlord, who arrives to collect the rent. They flatter him and ply him with wine. In his drunkenness, he begins to boast of his amorous adventures, but when he also reveals that he is married, they thrust him from the room—without the rent payment—in comic moral indignation. The rent money is divided for their evening out in the Quartier Latin.
Marcello, Schaunard and Colline go out, but Rodolfo remains alone for a moment in order to finish an article he is writing, promising to join his friends soon. There is a knock at the door. It is a girl who lives in another room in the building. Her candle has blown out, and she has no matches; she asks Rodolfo to light it. She is briefly overcome with faintness, and Rodolfo helps her to a chair and offers her a glass of wine. She thanks him. After a few minutes, she says that she is better and must go. But as she turns to leave, she realizes that she has lost her key.
Her candle goes out in the draught and Rodolfo's candle goes out too; the pair stumble in the dark. Rodolfo, eager to spend time with the girl, to whom he is already attracted, finds the key and pockets it, feigning innocence. He takes her cold hand (Che gelida manina—"What a cold little hand") and tells her of his life as a poet, then asks her to tell him more about her life. The girl says her name is Mimì (Sì, mi chiamano Mimì—"Yes, they call me Mimì"), and describes her simple life as an embroiderer. Impatiently, the waiting friends call Rodolfo. He answers and turns to see Mimì bathed in moonlight (duet, Rodolfo and Mimì: O soave fanciulla—"Oh lovely girl"). They realize that they have fallen in love. Rodolfo suggests remaining at home with Mimì, but she decides to accompany him to the Cafe Momus. As they leave, they sing of their newfound love.
Act 2
Quartier Latin (same evening)
A great crowd, including children, has gathered with street sellers announcing their wares (chorus: Aranci, datteri! Caldi i marroni!—"Oranges, dates! Hot chestnuts!"). The friends arrive; Rodolfo buys Mimì a bonnet from a vendor, while Colline buys a coat and Schaunard a horn. Parisians gossip with friends and bargain with the vendors; the children of the streets clamor to see the wares of Parpignol, the toy seller. The friends enter the Cafe Momus.
As the men and Mimì dine at the cafe, Musetta, formerly Marcello's sweetheart, arrives with her rich (and elderly) government minister admirer, Alcindoro, whom she is tormenting. It is clear she has tired of him. To the delight of the Parisians and the embarrassment of her patron, she sings a risqué song (Musetta's waltz: Quando m'en vo'—"When I go along"), hoping to reclaim Marcello's attention. The ploy works; at the same time, Mimì recognizes that Musetta truly loves Marcello. To be rid of Alcindoro for a bit, Musetta pretends to be suffering from a tight shoe and sends him to the shoemaker to get her shoe mended. Alcindoro leaves, and Musetta and Marcello fall rapturously into each other's arms.
The friends are presented with their bill. However, Schaunard's purse has gone missing and no one else has enough money to pay. The sly Musetta has the entire bill charged to Alcindoro. The sound of a military band is heard, and the friends leave. Alcindoro returns with the repaired shoe seeking Musetta. The waiter hands him the bill and, dumbfounded, Alcindoro sinks into a chair.
Act 3
At the toll gate at the Barrière d'Enfer (late February)
Peddlers pass through the barriers and enter the city. Mimì appears, coughing violently. She tries to find Marcello, who is currently living in a little tavern where he paints signs for the innkeeper. She tells him of her hard life with Rodolfo, who abandoned her the night before, and of Rodolfo's terrible jealousy (O buon Marcello, aiuto!—"Oh, good Marcello, help me!"). Marcello tells her that Rodolfo is asleep inside, and expresses concern about Mimì's cough. Rodolfo wakes up and comes out looking for Marcello. Mimì hides and overhears Rodolfo first telling Marcello that he left Mimì because of her coquettishness, but finally confessing that his jealousy is a sham: he fears she is slowly being consumed by a deadly illness (most likely tuberculosis, known by the catchall name "consumption" in the nineteenth century). Rodolfo, in his poverty, can do little to help Mimì and hopes that his pretended unkindness will inspire her to seek another, wealthier suitor (Marcello, finalmente—"Marcello, finally").
Out of kindness towards Mimì, Marcello tries to silence him, but she has already heard all. Her weeping and coughing reveal her presence, and Rodolfo hurries to her. Musetta's laughter is heard and Marcello goes to find out what has happened. Mimì tells Rodolfo that she is leaving him, and asks that they separate amicably (Mimì: Donde lieta uscì—"From here she happily left"); but their love for one another is too strong for the pair to part. As a compromise, they agree to remain together until the spring, when the world is coming to life again and no one feels truly alone. Meanwhile, Marcello has found Musetta, and the couple quarrel fiercely about Musetta's flirtatiousness: an antithetical counterpoint to the other pair's reconciliation (quartet: Mimì, Rodolfo, Musetta, Marcello: Addio dolce svegliare alla mattina!—"Goodbye, sweet awakening in the morning!").
Act 4
Back in the garret (some months later)
Marcello and Rodolfo are trying to work, though they are primarily talking about their girlfriends, who have left them and found wealthy lovers. Rodolfo has seen Musetta in a fine carriage and Marcello has seen Mimì dressed like a queen. The men both express their nostalgia (duet: O Mimì, tu più non torni—"O Mimì, will you not return?"). Schaunard and Colline arrive with a very frugal dinner and all parody eating a plentiful banquet, dance together and sing, before Schaunard and Colline engage in a mock duel.
Musetta suddenly appears; Mimì, who took up with a wealthy viscount after leaving Rodolfo in the spring, has left her patron. Musetta found her that day in the street, severely weakened by her illness, and Mimì begged Musetta to bring her to Rodolfo. Mimì, haggard and pale, is assisted onto a bed. Briefly, she feels as though she is recovering. Musetta and Marcello leave to sell Musetta's earrings in order to buy medicine, and Colline leaves to pawn his overcoat (Vecchia zimarra—"Old coat"). Schaunard leaves with Colline to give Mimì and Rodolfo some time together. Mimì tells Rodolfo that her love for him is her whole life (aria/duet, Mimì and Rodolfo: Sono andati?—"Have they gone?").
To Mimì's delight, Rodolfo presents her with the pink bonnet he bought her, which he has kept as a souvenir of their love. They remember past happiness and their first meeting—the candles, the lost key. Suddenly, Mimì is overwhelmed by a coughing fit. The others return, with a gift of a muff to warm Mimì's hands and some medicine. Mimì gently thanks Rodolfo for the muff, which she believes is a present from him, reassures him that she is better and falls asleep. Musetta prays. Schaunard discovers that Mimì has died. Rodolfo rushes to the bed, calling Mimì's name in anguish, weeping helplessly as the curtain falls.