“Them” (Penguin Press, 530 pages, $29.95) is the book that Francine du Plessix Gray was born to write. This is not to say that Ms. Gray’s other books – novels, biographies of the Marquis de Sade and Simone Weil – were just warm-ups for this brilliant and moving memoir. But as Ms. Gray unfolds the story of her maddening, seductive parents – a story that embraces Russia, France, and America, literature, art and high society, the superficial glamour of fashion magazines, and the deep scars of the family romance – it becomes clear why she had to wait until she was in her 70s to write the story of her childhood. To escape the gravitational pull of her parents was the work of a lifetime. Not until her mother and stepfather were dead, and their ghosts laid, could she have produced “Them,” a book that is at once a filial tribute and a final emancipation.

For all of us, perhaps, our parents remain the permanent “them,” so constant a presence that the pronoun – uttered in tones of exasperation, familiarity, or love – can refer to no one else. But few children have to deal with a “them” as overwhelming as Ms. Gray’s. Her mother, Tatiana Yakovleva, was one of mid-century New York’s leading fashion icons, the hat designer for Saks at a time when hats were big business. Ms. Gray’s stepfather, who raised her from the age of 10, was Alexander Liberman, whose ascent from art director of Vogue to editorial boss of Conde Nast made him one of the most powerful figures in New York publishing. In their townhouse at 173 East 70th Street, they attracted a glamorous set to what were, in Ms. Gray’s words, “New York’s first ‘power lunches’ in the contemporary sense of that phrase” – Salvador Dali, Christian Dior, and Marlene Dietrich were all guests.

Even before they reached this social Olympus in the 1950s and 1960s, however, Tatiana and Alex, as Ms. Gray calls them, had already lived through enough experiences for a whole biography. The course of both their lives was determined by the Russian Revolution, which like a world-historical centrifuge sent refugees whirling across the planet. Tatiana, who was born in 1906 to a mother from a theatrical family and an engineer father, saw her parents separate during the World War I. After the revolution, she managed to join emigre relatives in Paris, where her uncle Sasha had cut a wide swath as an artist and African explorer.

It was in Paris that she met the great love of her life, the famous poet of the Revolution, Vladimir Mayakovsky; Tatiana was the inspiration of some of his best love poems, earning herself a secure place in Russian literary history. (When Ms. Gray first traveled to the Soviet Union, she was shocked to find baby pictures of herself in the Mayakovsky Museum.) But Mayakovsky was fated to return to the USSR, where he would eventually commit suicide, disillusioned by the party that had exploited him. Tatiana went on to make a good match with Bernard du Plessix, a French diplomat from a poor but ancient family; Francine, their only child, was born in 1931, just nine months and two days after the wedding.

But Bernard was not to become the other great presence in his daughter’s life, the second member of “Them.” By the time he died a hero’s death in 1940 – shot down while flying to London to join De Gaulle’s Free French movement – he and his wife had already become estranged. And his death, in an awful irony that was to haunt his daughter’s life, made possible Tatiana’s extremely close and durable marriage to the man she already loved: Alexander Liberman.

Alex, too, was born in Russia, in 1912, to a Gypsy actress mother and a Jewish father prominent in the lumber business. Semyon Liberman, an active Menshevik, had expertise that made him indispensable to Lenin in the first years after the revolution, when technical knowledge still outweighed ideological purity. By the mid-1920s, however, the Libermans had also left Russia for France, where Alex’s path intersected with Tatiana’s. Their love affair, played out against the beginning of World War II and the fall of France, seems positively cinematic. Only their lifelong good luck allowed them to reunite and make their way to New York, with 9-year-old Francine in tow, in the great wave of refugees that also included Simone Weil and Hannah Arendt.

But these epic lives are just the first part of the story Ms. Gray has to tell. Once in America, historical tragedy gives way to family drama, and to the light comedy of the fashionable world. And here is where the honesty and rigor of Ms. Gray’s book become crucial. With Freudian patience, she seeks to arrive at some kind of objectivity about the two people who created her childhood, both saving her life and damaging her in all kinds of improbable ways. Tatiana, it becomes clear, was perfectly unmaternal, unable to deal even with her daughter’s first period, much less with breaking the news of Bernard du Plessix’s death – a task she delegated to the babysitter. (It is characteristic of the Libermans’ milieu that even the babysitter turns out to be Gitta Sereny, the future biographer of Albert Speer.)

The subtle ways Tatiana made war on her daughter’s sexuality and self-esteem – resulting in what sounds very like a case of teenage anorexia, though Ms. Gray does not call it that – are recorded with surprisingly little rancor. It is Alex, the family’s arbiter and protector, who comes in for Ms. Gray’s bitterest criticism. The one part of the family story she does not seem ready to forgive is the way Alex ruthlessly cut her out of his life after Tatiana died; the nurse who he went on to marry is the target of Ms. Gray’s sharpest barbs. Neither of “Them” come across in Ms. Gray’s portrait as likable – they are both ambitious, disloyal, self-centered, unkind. But unlike so many children, Ms. Gray is able to see her parents as actual people, not demigods or malign fates; she is able to understand and even forgive them. This act of sympathy, still more than the richness of the story she has to tell, is what makes “Them” such a compelling and fascinating book.