Well, that was crappy. Things do happen in this novel, and yet, it somehow manages to be completely anticlimactic. How? Everything important happens "off-screen" to characters Leroux never bothered to even consider that someone would want to read about, despite being the lead characters in the novel...
If you've seen the musical or movie you know the story - Opera Ghost terrorizes managers and presents himself as an Angel of Music to the up and coming Christine Daae. He gives her lessons and tries to make her fall in love with him with some success. But then Christine's childhood friend, Raoul, ...
Great old gothic mystery! The most interesting "character" is the opera house.