Assassin's True Name is the Phantom of the Opera (ファントム・オブ・ジ・オペラ, Fantomu obu ji Opera). A masked killer. The mysterious person who appeared in “The Phantom of the Opera”, a novel set in the 19th Century――perhaps, the person who became its model. Settling down and inhabiting in an aqueduct that is like a vast underground labyrinth beneath the opera house (Palais Garnier), he was charmed by a young and chaste actress who was viewed as purity itself, even guiding her into becoming a diva, and conducted serial murders on behalf of his unfulfilled love.