Aldemaro, a young nobleman of a noble but impoverished family, arrives in the city of Tudela with his cousin Ricaredo for the wedding of Feliciana, the daughter of one of the most famous and wealthy citizens, and immediately falls in love with the newlywed's sister, Florella. The feeling that struck him unexpectedly is so great that he flatly refuses to leave Tudela and return to the ancestral castle of Lerin. Despite all the exhortations of Ricaredo, Aldemaro firmly decides that he will be hired by Alberigo, the father of Feliciana and Florela, a dance teacher: the young man recently returned from Naples, where he learned this art so much that he could compete with Italians.
Just at that time, Feliciana, her husband Tevano, Florela and Alberigo were discussing the festivities that had just ended. It was a success: a knightly tournament, competitions in strength and dexterity, a masquerade procession, each participant of which showed miracles of ingenuity, and many other entertainments. Only one thing saddens young women: among all the entertainments there was clearly not enough dancing, and they bitterly complain to their father about their inability to dance, reproaching him for not teaching them this art. Alberigo immediately decides to correct his mistake and hire a teacher; here Aldemaro comes, posing as a dance teacher. He is very popular with all members of the family, especially Florele, who immediately falls in love with him. The girl is famous for her beauty - at the just-concluded festival, many, including the noble and beautiful nobleman Vandalino, piled their prizes at her feet as a sign of admiration.
Vandalino had long been in love with Florela, and at the wedding of her sister, he dared, passing Florela a case with his prize, to put a love message in it. Now the young man hopes to get an answer and, having learned that Alberigo has hired a dance teacher for his daughters, he turns to him with a request to become an intermediary between him and Florella. Aldemaro agrees, hoping in this way to find out how Florela relates to a passionate admirer and evaluate whether he himself has hope for success. It turns out that Feliciana’s happiness is not as great as it seemed to the guests at her wedding: she does not love her husband and married him only obeying her father’s will. She is clearly jealous of her sister, whom Vandalino is in love with - this young, refined nobleman really likes the newlywed. Upon learning that he dared to convey a love message to Florele along with the prize, Feliciana begs her sister to agree to meet with her fan, and at night she will go out to the balcony to talk to him - he still does not know their voices and will easily accept one sister for another. For his part, Aldemaro decides to spy on this date to find out if Florela responds to her admirer's feelings. He, like Vandalino, is deceived, accepting Feliciana, who favorably listens from the balcony to the passionate confessions of Vandalino standing below, for Florela.
The unfortunate Aldemaro can not restrain his emotions and, giving Florele the next day a dance lesson, declares her love. Fortunately, he suddenly finds out that he is reciprocated. Florele becomes aware that Aldemaro belongs to a noble family and that only love for her forced him to become a dance teacher. She herself confesses to him that her sister was standing on the balcony at night, and explains how and why she was there. The conversation of young people is interrupted by the arrival of Feliciana, who managed to write a love message from Vandalino on behalf of Florela, putting her own feelings and desires into it. Florela instructs Aldemaro to deliver this letter to the addressee: now the young man is aware of the game played by the sisters, and willingly undertakes to fulfill this assignment.
Florelle is somewhat worried that she does not know the content of the love message written on her behalf, and Felisyan in every possible way avoids the direct answer. However, Aldemaro himself learns from Vandalino that he is scheduled to meet in the garden at night. When Florele becomes aware of this, she is indignant at the ease with which her sister jeopardizes her honor. After reading Vandalino’s response to Feliciana’s note, Florela tears it up with anger and replaces it with another, in which Vandalino refuses to go on an appointment for him, because he sees the future wife and not his mistress in the subject of his passion, and promises to wait for her, like last night under the window. It is this response that Aldemaro conveys to the Felicians, who are extremely offended by the indifferent tone of the message. Aldemaro decides, along with two servants, to trap Vandalino at night under the window and teach him a lesson. In turn, Tevano, the husband of Feliciana, having found fragments of the letter torn by Florella, suspects that it was addressed to his wife, and also decides to spend the night in the garden in order to track down the intruder. On a date, Floreda goes out to the garden at night, who reveals the truth to Vandalino: she never wrote to him, and, most likely, some duet made fun of him. In the dark of night, Aldemaro, who was about to teach a lesson to Florence's ardent admirer, mistook Tevano for an attacker and almost wounded him.
Meanwhile, the offended Felisyana decides to speak with Vandalino, who assures him that he never wrote Florele indifferent messages and did not refuse night visits. Realizing that Aldemaro is behind this fraud, Felisyana decides to take revenge: she orders the butler, who does not have much love for the dance teacher because of his exquisite manners, and therefore will be silent, put a jewelry box in Aldemaro’s room. She writes on behalf of her sister the message of Vandalino, in which Florela allegedly confirms her intention to come to him on a date at night and promises to become his wife. Felician shows miracles of ingenuity, passing this note to Vandalino right in the presence of Tevano, her husband. Left alone, Felisyana, under some pretext, asks to bring her jewelry, and then their loss is revealed. A butler sent in search soon brings a jewelry box, which was discovered in the dance teacher's room. The angry landlord, Alberigo, orders the servants to take the sword from Aldemaro and take him to prison. The artful Belardo, the servant of Aldemaro, managed to slip away. He rushes to the search for Ricaredo, who returned to Tudela, hoping to persuade his cousin to return to his father's shelter. Grabbing another servant, Ricaredo and Belardo head to the house of Alberigo, where they penetrate undetected.
In the meantime, Florela, in order to save her lover, explains to her father that she never loved Vandalino and that the intercepted letter in which she makes an appointment in the garden that night is false. Afraid that if the truth comes out, Felician will be disgraced, Alberigo begs Florela to marry Vandalino and save her sister and the whole family from shame. However, the resourceful Florela even here comes up with a way out: she tells her father how to behave with Vandalino, and even Alberigo is amazed at the ingenuity of her daughter. Not wanting to force Florella to marry an unloved person, he tells Vandalino that he does not dream of anything else but to see him with his son-in-law, but the reckless Florela decided to secretly get married to a dance teacher and introduce him into her father's house under a false name. Then she changed her mind, and now her hand is free - Alberigo will happily betray her daughter for Vandalino. The heard strongly embarrasses the recently passionately in love young man: he does not want to disgrace his family by marriage with a woman who could behave so unworthily, cannot imagine such a woman as the mother of his children. And Vandalino without hesitation refuses the honor of becoming Alberigo's son-in-law. While this explanation went on, Florela removed the shackles from Aldemaro, who was sitting under the castle, and Ricaredo and his companions who entered the house almost grabbed swords from Tevano.
Alberigo announces to all those present that Vandalino refused to claim Florela’s hand and that, knowing the nobility of the family from which Aldemaro comes, he will happily give his daughter away. Servant Aldemaro Belardo is married to Liceno, the handmaiden of Florela, for whom Alberigo gives a generous dowry, and Feliciana has no choice but to erase love of Vandalino from her heart.
