The Prologue opens with a narrative frame in which the narrator says he will explain the mysterious events at the Opera House. This frame creates a sense of place in history and a sense of reality around an otherwise fantastic story. The story returns to its frame in the Epilogue, as the narrator suggests a tantalizing bit of fictional history in its first footnote:
I mentioned this undertaking again to M. Dujardin-Beaumetz, our gracious under-secretary for Fine Arts, only forty-eight hours before the publication of this book [...] I told him that the state had a duty to dispel the legend of the Phantom of the Opera and establish the facts of Erik’s existence. But for that we need – and this would be the culmination of my investigation – to gain access to his lair. Musical treasures may still be buried there.
In this scene, it becomes clear that even to the man who wrote an entire book about him, the Phantom remains a mysterious figure. The frame story has a dual function; in the beginning, it grounds the reader in a fictional reality, and in the end, it suggests that no matter how much grounding research one might do, one could never know the full extent of the Phantom's mysterious existence.
