The Phantom of the Opera is written in realistic, straightforward, and sometimes grandiose prose. Leroux provides detailed character descriptions, especially of the Phantom, whose face few have glimpsed but most fear. He treats the opera house with the same attention to detail; each scene includes some mention of secret rooms, trapdoors, or chambers.
The novel's straightforward prose makes the story's fantastical events seem more believable, which heightens the impact of its darker and more violent scenes. Sometimes euphemism is used, as in Chapter 17 when the narrator reveals a conspiracy between the Phantom and the opera house:
I have previously had occasion to say that the directors’ mood had taken a disagreeable turn, and have suggested that this might not have been solely caused by the fall of the chandelier. Reader, let me tell you now what the directors would rather have kept forever a secret: sometime before the fateful night of Christine’s disappearance, the Phantom of the Opera had been quietly paid his first twenty thousand francs.
Here, the phrase "disagreeable turn" refers lightly to a dramatic shift in the director's mood. The euphemistic, formal description mirrors the fake professionalism of the director and his cronies. A profusion of euphemisms at the beginning of this paragraph contrasts sharply with the stark, descriptive sentence about illicit payments to the Phantom.
