Gasparina, the songstress, and her mother, Apollonia, are visited by Don Ettore, a young man who attempts to woo Gasparina with fabric and jewels stolen from his mother. When Don Pelagio, Gasparina's singing instructor and benefactor, arrives, the women attempt to disguise Don Ettore as a merchant and send him away. Don Pelagio teaches Gasparina a new aria he has written for her and asks her to marry him.
When Don Pelagio leaves, Gasparina calls Don Ettore back in. Don Pelagio has left something behind, however, and returns to catch Gasparina and Don Ettore together. Don Pelagio and Don Ettore are both angry at having been deceived and taken advantage of by the women. Don Pelagio decides to throw the women out of their apartment, which he had given them, and begins to carry away their belongings.
Gasparina pleads for forgiveness and mercy, and Don Pelagio is swayed. Not only does he allow her to stay in the apartment, but he brings his own belongings to the women. Gasparina continues to take advantage of the situation, pretending to faint. The men lavish her with money and diamonds, which have a curiously restorative effect. In the end, the men recognize Gasparina's greed, but nonetheless willingly hand over their riches.
The comic potential is enhanced by Don Ettore being played as a Breeches role – that is, by a woman. The soprano role of Apollonia was originally sung by a man.
There are two quartets, and all characters but Don Ettore have arias to sing.
