The Age of Innocence by Edith Wharton

From The Guardian:

The-Age-of-Innocence-001 When Newland Archer opened the door at the back of the box, the curtain had just gone up on the garden scene. “Darn it,” he thought. “I have arrived 10 seconds unfashionably early. All New York knows you are not supposed to make your entrance until Marguerite is two bars into her aria.” Newland's annoyance dissipated when he realised that no one who was anyone in New York society had witnessed his horrendous faux pas. During the interval he turned his gaze towards his beloved, the divine May Welland, seated in the Mingott box opposite, and frowned when he saw that her cousin, the Countess Ellen Olenska, was in her party. How very awkward! What would New York think of the reintroduction of the scarlet woman into society? Yet how typical of the Mingotts to be so brazenly protective of their own! No matter! He would rise above New York's pettiness and his reputation would be unstained!

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