The curtain opens on the entrance of a village. A chorus of villagers sing of their excitement at the arrival of the commedia dell'arte troupe. Canio announces that the evenings performance will commence at 11pm and has almost left for a drink when a villager jests that Canio's wife, Nedda, might not be safe from Tonio's affections while he is gone. Canio immediately gets defensive, and sings "Un Tal Gioco"; explaining that while it may be funny to watch on stage, such a situation in real life would be better not to contemplate.
After he has left, Nedda sings to herself. She is surprised to discover Tonio listening. He expresses adoration for her, to which she responds with scorn. He grows more insistent, until she fights him off with a whip. Sylvio, Nedda's lover, arrives on the scene, and has convinced Nedda to run off with him that night, when they are surprised by Canio, who has been brought back by a vengeful Tonio. Sylvio escapes, but Canio threatens Nedda at knifepoint to reveal the name of her lover. Beppe intervenes, and reminds them that the performance must start shortly. Canio relents, but sings "Vesti la Giubba"; expressing the deep distress of having to surpress his grief and anger to play the clown.
Everyone arrives for the show after a brief intermezzo. As the play commences, anyone not familiar with the conventions of commedia dell'arte becomes quickly aware how dangerously close the lives of the actors have been to the roles they play. Columbina (Nedda) is serenaded by her lover Arlecchino (Beppe) but, while waiting for him, Taddeo (Tonio) arrives and makes advances to her. She spurns him, and Arlecchino soon arrives and gets rid of him. They are surprised, however, when Pagliaccio (Canio) arrives home early. Canio is unable to contain himself, and again starts pressing Nedda for the name of her lover. She tries to lead him back to his role, as the chorus comments on how "real" the play seems, but he refuses and grows more and more angry. When she refuses to give the name of her lover, he grabs a knife from the table and stabs her. Sylvio, who has been sitting in the audience, jumps up at her cry for help, and Canio stabs him as well. At this point either Canio or Tonio (depending on whether tradition or authenticity has the upper hand) speaks the final line: "La commedia e finita" ("the comedy is ended").
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The End of the Comedy?
Where does meaning begin and end? The expositional nature of the prologue takes the audience on a journey which finally ends when Tonio says: "La commedia e finita!" (The comedy is ended!), the audience is challenged with two conflicting ideas-have we as the audience just witnessed the death of the protagonists, or the death of the singers actual self? What actually constitutes self? Leoncavallo show us that self is simply the putting on of roles and discarding of roles. Ultimately, our selves are defined by the confinements of the role we step into.