The novel opens with a prologue in which Gaston Leroux claims that Erik, the "Phantom of the Opera", was a real person. We are then introduced to Christine Daaé. She and her father, a famous fiddler, traveled all over Sweden playing folk and religious music. Her father was known to be the best wedding fiddler in the land. When Christine is six, her mother dies and her father is brought to rural France by a patron, Professor Valerius.
During Christine's childhood, which is described retrospectively in the early chapters of the book, her father tells her many stories featuring an 'Angel of Music', who, like a muse, is the personification of musical inspiration. Christine meets and befriends the young Raoul, Viscount of Chagny, who also enjoys her father's many stories. One of Christine and Raoul's favorite stories is one of Little Lotte, a girl with golden hair and blue eyes who is visited by the Angel of Music and possesses a heavenly voice.
Christine is eventually given a position in the chorus at the Paris Opera House (Palais Garnier). Not long after she arrives there, she begins hearing a beautiful, unearthly voice which sings to her and speaks to her. She believes this must be the Angel of Music and asks him if he is. The Voice agrees and offers to teach her "a little bit of heaven's music." The Voice, however, belongs to Erik, a deformed genius who was one of the contractors who built the opera and who secretly built a home for himself in the cellars. He is the Opera ghost ("Fantôme" in French can be translated as both "ghost" and "phantom") who has been extorting money from the Opera's management for many years. Unknown to Christine, at least at first, he falls in love with her.