The Phantom of the Opera is set at the Paris Opera House, also known as Palais Garnier. The real-life opera house was opened in 1875 and was designed by Charles Garnier. It was commissioned by Napoléon III in reaction to an assassination attempt because he wanted to leave his mark on the architecture of Paris. The building itself is opulent, and several key locations are featured in the book, including the stage area and the “lake that exists in the lower cellars of the Opera on the Rue-Scribe side.”
Leroux describes the interior of the opera house as “huge” and “gloomy”. He continues:
A few rays of light, a wan, sinister light, that seemed to have been stolen from an expiring luminary, fell through some opening or other upon an old tower that raised its pasteboard battlements on the stage; everything, in this deceptive light, adopted a fantastic shape...At the top, right on top of the cliff, lost in M. Lenepveu's copper ceiling, figures grinned and grimaced, laughed and jeered at MM. Richard and Moncharmin's distress. And yet these figures were usually very serious. Their names were Isis, Amphitrite, Hebe, Pandora, Psyche, Thetis, Pomona, Daphne, Clytie, Galatea and Arethusa.
The opera house, when empty, is unnerving and sinister. Christine, one of the main characters, describes the passage to the lake beneath the opera house as filled with “darkness”, but she is then blinded by “a dazzling light” on the shore of the lake. The physical setting of the novel helps set the mood for a plot filled with grim and thrilling twists.
The readers learn at the beginning of the novel that “the events do not date more than thirty years back” from when Leroux is writing his story. The work was published serially in 1910, which puts the events of the novel in the early 1880s. This indicates that the events of the novel would have taken place shortly after the Paris Opera House opened.