Lyric discussion by 42 steps 

I agree that this beautiful song is meant to be a call to the heroine, a temptation. A seduction, not only of the physical sort, but also a seduction of the mind. I think that the choice to be made is a... lifestyle choice, essentially.

The song is meant to be an appeal to Christine's imagination, to turn away from one's practical side and give into the impractical, the dark, the beautiful/ugly. To live outside the boundaries of the (every)day. A call to the artist(?)inside.

The eventual showdown between the Phantom and Raoul (in addition to the surface action) represents a real struggle for Christine's psyche, to give herself entirely to the shadowy world of the artist/performer; or to live the traditional, private role as an upper-class wife of that era.

When Christine makes her final decision to flee the opera house with Raoul, we are left with the impression that she's left a part of herself behind, the diva/prima donna that she might have been. I personally get the impression that she will never perform professionally again.

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