After the overture, in the Prologue, the chorus tells about the feud between the Montagues and the Capulets, two noble families from Verona, and speaks about the love that the Montague Romeo and the Capulet Juliet feel for each other.

The first act opens with a ball in the Capulet palace. Two young nobles, Tybalt and Paris, are chatting and we find out that Juliet, Capulet’s daughter, is getting engaged to Paris. Capulet enters and presents his daughter to those attending the ball. When the dancers leave, some Montagues, who have attended the ball wearing masks, are left alone. Amongst them are Romeo and his friend Mercutio. The former has the feeling that a danger is lurking, but Mercutio teases him, saying that Romeo’s sadness is due to the fact that Rosaline is not there, but he will forget her as soon as he sees the beautiful girls who have come to the ball. Romeo sees Juliet and is immediately fascinated by her. Mercutio states that Romeo seems to have already forgotten his Rosaline.

Juliet meets Gertrude, her nurse, who mentions her engagement to Paris, but the young girl tells her about her wish to enjoy youth for as long as she can. Later, Romeo and Juliet meet alone for the first time. Romeo praises her beauty but she confidently dodges his compliments. He asks her who she is and, to his dismay, she tells him that she is Capulet’s daughter. Tybalt approaches, tells Juliet not to leave the ball aside and asks her who she is talking to (when Tybalt was approaching, Romeo put his mask on to hide his identity), but she says that she doesn’t know. Romeo bids farewell to Tybalt with scathing courtesy and as he recognizes his voice he vows to seek revenge.

Juliet now understands who Romeo is and is horrified at having fallen in love with an enemy of her family. When Romeo reappears, he is greeted by Tybalt and Paris, after which there are hostile exchanges between the groups of Montagues and Capulets, while Capulet tries to make the festive atmosphere continue.

The second act starts in Juliet’s garden. Romeo arrives and shortly afterwards Juliet appears on the balcony, lamenting her love for a member of the Montague family. Romeo announces himself and declares his love to her, but when she hears some footsteps approaching she asks him to hide. A group of Capulet servants, led by Gregorio, are looking for a page of the Montagues who has been seen lurking around. After going around the garden, they tease Gertrude, asking if she is the reason why a Montague has been so bold. The servants leave and Gertrude convinces Juliet to go inside. She takes her advice but soon after she returns to the garden, where the love duet continues until the lovers say good-bye until the next day.

In the first scene of the third act we see the cell of Friar Laurent, a Franciscan monk. After an intermission, Romeo enters and asks the monk to marry him to Juliet. The ceremony takes place while Gertrude stays outside, watching by the door. In the second scene the action moves to the Capulet palace. Romeo’s page is looking for his master. A group of Capulets, led by Gregorio, leaves the palace and the page mocks them. Mercutio enters and starts to fight with Tybalt, but Romeo separates them. Tybalt insults him, but Romeo manages to control himself, as he remembers that Tybalt is a relative of Juliet and says that the time to hate each other is over. Mercutio is shocked by Romeo’s refusal to fight and he himself attacks Tybalt. After Mercutio falls dead, Romeo, set off by his anger, mortally wounds Tybalt. Capulet enters and Romeo realizes, to his dismay, that his killing Tybalt may gain him Juliet’s hatred. Before dying, Tybalt expresses his last wish to Capulet, which cannot be heard by the rest.

Capulet resorts to the Duke to do justice. Romeo justifies himself saying that Tybalt had killed Mercutio before. The Duke reprimands both families and exiles Romeo. At the end of the act, Romeo expresses his firm desire to see Juliet again, while the Capulets, ignoring the Duke’s request for peace, claim revenge against the Montagues.
The fourth act opens in Juliet’s chambers; she forgives Romeo for having killed Tybalt and declares her love to him again. It starts to dawn and Juliet tells him that he has to leave the house. He leaves through the balcony, where Juliet stays praying for him to be able to escape safe and sound. Gertrude enters and, very agitated, says that Juliet’s father is approaching. He enters with Friar Laurent and tells his daughter that she has to marry Count Paris immediately, as this was the desire that Tybalt entrusted him with before dying. Capulet leaves to welcome the guests to the wedding and, when alone with Friar Laurent, Juliet begs him to help her. The friar gives her a vial with a liquid and tells her that, when she drinks it, she will fall into a sleep so deep that everyone will think that she is dead, but she will only be like that for one day.

Friar Laurent promises that he will be near her when she comes back to life and will help her escape with Romeo. Juliet drinks the potion and Capulet returns with Paris, Gertrude and their entourage. He tells her about the pleasures awaiting her as a bride. She replies that her wedding bed will be her grave and falls onto the floor upon fainting.
The Capulet family’s tomb is the stage of the fifth act. An orchestral interlude describes Juliet`s dream. Romeo, who already knows that Juliet has died, enters. He observes her, admiring her beauty, and deliriously embraces her, after which he drinks a poison. When he is falling as a consequence of its effects, he sees in astonishment that Juliet is starting to wake up. She pronounces his name and, enraptured, he asks her to flee together. But he cannot escape the effects of the poison he has drunk and has to confess that his life is coming to an end. Distressed, she also asks for some poison but, as she has none, she stabs herself. The two lovers have finally reunited in death.