In 1913, Vienna's Carltheater commissioned Giacomo Puccini, the master of Italian verismo, to write a Viennese Operetta a la Lehar. Four Years later, the result was La Rondine, the Swallow. In the process, Puccini quickly tossed the first libretto and the operetta convention of dialogue between numbers. And he never had liked dancing in his operas, so dancing was out too. There are operetta reminders with the waltzes and what some consider it's frothy, inconsequential main plot, and a sub-plot that includes a vivacious maid wearing her mistresses dress to a party, but the conflict of Puccini’s style and the conventions of operetta was never quite resolved, though the result is filled with beautiful music.
The story is similar to that of Manon Lescaut with a little of La Traviata thrown in.
The setting is Paris in the 1920s. Magda is the mistress of the rich and much older Rambaldo. As Act I begins, They are giving a party. A poet, sings a song he is composing about romantic love, Chi il Sogna di Doretta, and how riches cannot give happiness. But it is not finished, and Magda adds a verse, showing how the revelation of an ardent kiss can bestow the true happiness the true happiness of reckless love that riches cannot.
This sets up the action - Magda, living in riches, finds romantic love, only to later lose it.
She finds it with Ruggero, a young man who appears at the party when she is out of the room - but who she later meets at the Café Bulier where they each have gone separately. They fall for each other instantly, and she tells Rambaldo, her older lover, that she is leaving him.
The young couple goes to a country villa, Magda, like the swallow flying South. Ruggero, who does not know of Magda’s past, happily tells her he has written to his father for money and permission to marry Magda. His mother writes with the permission, so long as Magda is worthy of him. The already conflicted Magda tells Ruggero she cannot marry him for his own good, and leaves him to return to Paris and Rambaldo.
La rondine premiered in Monte Carlo in 1917, not Vienna, because of WW1. It was to be Puccini's next to last full length opera.