Bushnell’s most-recent novel, “One Fifth Avenue,” is a modern-day story of old and new money, the always combustible mix that Edith Wharton mastered in her novels about New York’s Gilded Age and that F. Scott Fitzgerald illuminated in his Jazz Age tales. Decades later, Bushnell’s New Yorkers suffer the same passions as those fictional Manhattanites from eras past: The thirst for power, for social prominence, and for marriages that are successful—at least to the public eye. “Here are bloggers and bullies, misfits and misanthropes, dear hearts and black hearts, dogfights and catty squalls spun into a darkly humorous chick-lit saga,” says Publisher’s Weekly.