It’s a long way from Park Avenue: the beautiful, desolate, casually despoiled landscape of the Pyrénées-Orientales in southernmost France, where Fernanda Eberstadt moved with her husband and children in 1998 and where she has set her latest novel. Eberstadt grew up in a fancifully ornate Upper East Side apartment with pistachio-green velvet walls, ancient statuary and a gold Marilyn by Andy Warhol in the living room, as she reminisced in The New York Observer in 2007. It was a childhood studded with glamour: in 1962 (little Fernanda was just 2 at the time) her parents — the photographer and psychotherapist Fredrick Eberstadt and the novelist Isabel Eberstadt — gave a legendary costume party at which Jacqueline Kennedy, flanked by Secret Service escorts, danced to a reggae band till dawn.

But throughout that gilded childhood, Eberstadt longed for another existence, for the footloose life of the willfully dispossessed. In her novels, idealists and fast-trackers wrestled with thorny problems of love and social identity. After her family’s move to the French countryside, her lifelong fascination with Gypsies inspired a nonfiction book about their haunted music and lives. “Flamenco,” she wrote, “is the art of desperate measures, the winning of a fugitive grace from failure, bankruptcy, shame.” That fugitive grace, that rag-picking of hope from ruin, resurfaces in Eberstadt’s shrewd and sensuous fifth novel, “Rat.”