Set in the 19th century France, there was a mysterious figure who lives in the catacombs of the Opera Populaire, named Erika or also known as the Phantom Girl of the Opera. She was deeply fell in love to a male singer named Christian Daae, her pupil. But somehow, he already have a love relationship with his childhood sweetheart, Raina De Chagny. Based from the Phantom of the Opera (both novel and musical adaptation).