The Phantom of the Opera by Gaston Leroux.
A disfigured man, known as the Phantom who loves to strike fear in the minds of the Paris Opera House staff, comes to a young singer, Christine Daae, and tutors her voice.

He falls in love with Christine and wants her for his own, but she only has eyes for Raoul Viscount de Chagny. The Phantom, feeling betrayed, kidnaps Christine and brings her to his lair where he plans to make her his eternal bride.

The Phantom of the Opera keywords: gaston leroux