Maskerade: (Discworld Novel 18)

Terry Pratchett

It's true, there's a ghost in the Opera House of Ankh Morpork. Sardonic, flamboyant and, well, ghostly, it wears a bone-white Mask and terrorizes the entire company, including the immortal Enrico Basilica, who eats continuously even when he's singing. Mostly spaghetti with tomato sauce. What better way...