The phantom of the opera - Poche

"It was the evening on which MM. Debienne and Poligny, the managers of the Opera, were giving a last gala performance to mark their retirement. Suddenly the dressingroom of La Sorelli, one of the principal dancers, was invaded by half-a dozen young ladies of the ballet, who had come up from the stage after "dancing" Polyeucte..." The Phantom of the Opera is a novel by French writer Gaston Leroux. It was first published as a serialisation in Le Gaulois from September 23, 1909, to January 8, 1910.
It was published in volume form in late March 1910 by Pierre Lafitte. The novel is partly inspired by historical events at the Paris Opera during the nineteenth century. Opera singer Christine triumphs at the gala on the night of the old managers' retirement. Her old childhood friend, Raoul, hears her sing and recalls his love for Christine. At this time, there are rumors of a phantom living at the Opera and he makes himself known to the managers through letters and malevolent acts.