Stacy Schiff is the author of many books. Her most recent is “The Witches: Salem, 1692,” out this month in paperback.

‘The dame has enormous dignity, she’s a person,” star Associated Press reporter Lorena Hickok wired her boss after the 1932 Democratic convention. She had had her eye for some time on Eleanor Roosevelt, who, she believed, would make better copy than a traditional first lady. Hickok lobbied hard for the White House beat; she wound up with more than she anticipated. Months later, on the eve of his inauguration, Franklin Roosevelt submitted his speech to Eleanor, in the hotel room next door, for her approval. She read those pages — she was among the first to hear that “the only thing we have to fear is fear itself” — aloud to Hickok, in Eleanor’s dressing gown, soon to be asleep in Eleanor’s bedroom. From the White House two nights later, the first lady apologized by letter to “Hick,” as she called her, after a phone conversation. As she had not been alone, it had not been possible to end the call with the customary “je t’aime et je t’adore.”

We have come a long way since a 1980 biography of Hickok that bypassed the women’s massive correspondence and dismissed the friendship as a “belated schoolgirl crush.” Today the relationship startles less for its intricate choreography than for its blithe simplicity: Six months into FDR’s first term, Hick and Eleanor escaped in Eleanor’s chrome-bumpered, light-blue convertible for a three-week tour of New England and Canada. They traveled with remarkable anonymity and without escorts. It was unlikely, Eleanor and Hick had assured the Secret Service, that they would be kidnapped. And if they were, where would anyone stash them? Eleanor was nearly six feet tall. Hick weighed almost 200 pounds. (“Lady, I get hungry,” the tough-talking Hickok explained when Eleanor commented on her weight.) Indeed, the Buick proved the primary attraction; only in a small Maine town, at the end of the trip, were the travelers recognized. Afterward they filled FDR in on the adventure over a three-person White House dinner.

To answer the question: No one knows precisely. Certainly it was a romance. As Quinn concedes mid-book, it may or may not have been an erotic one. For the next 12 years Hick largely lived at the White House; she sent her laundry there when on the road. Early on, Eleanor arranged for her to travel the country to take the pulse of Depression America for a federal agency. She pelted Hick with letters, to the point that her correspondent called for a moratorium on ostentatious White House stationery. The two women thought of each other in church, before they fell asleep, all day long. Hick wrote to Eleanor: “I want to put my arms around you and kiss you at the corner of your mouth.” Eleanor yearned to lie with Hick in her arms. She wore a ring Hick gave her. The two made a point of spending Christmas together, if not always on Dec. 25. The arrangement nearly fell apart only in 1941, when an annoyed Eleanor rescheduled at the last minute. No one had told her Winston Churchill was coming.

Eleanor did not strike relatives as a woman much given to physical intimacy; the mother of six would warn a daughter that sex was an ordeal. Having discovered her husband’s infidelity, Eleanor had agreed to remain in the marriage but not in FDR’s bed. She later maintained that mutual interests meant more to a marriage than sexual satisfaction. Ultimately with Hick, the form of intimacy mattered little: The ex-reporter was for years Eleanor’s emotional anchor, her most trusted correspondent, her eyes, ears and spine. It was in her that Eleanor confided her dislike of politics, the infighting and adulation, the scrutiny and scheming. “Why can’t someone have this job who’d like it & do something worth while with it?” America’s most beloved first lady asked Hick at the beginning of FDR’s second term.

"Eleanor and Hick: The Love Affair That Shaped a First Lady" by Susan Quinn (Penguin Press )

Quinn is not the first to examine the two women’s romance; most notably, biographers Blanche Wiesen Cook and Hazel Rowley have covered the territory. Quinn is the first to devote a full volume to the relationship, however, detailing its ramifications for the White House and for Eleanor. Hick’s reports from the field informed New Deal policy. She taught the first lady how to handle the press; she encouraged her to write her syndicated column, which grew from their correspondence. Quinn argues that Hick — who could turn out seven political speeches in 48 hours — made Eleanor a better writer. Certainly Eleanor got the better deal. She arranged several positions for Hick, including one at the Works Progress Administration, but essentially ruined her reportorial career, “the only thing I ever was really good at,” as Hick sighed later.

Quinn has produced an intimate book, tender and wise. She is strangely silent on only one count: She offers no sense of what, if anything, FDR knew or whether it mattered. Eleanor made a point of being everywhere for everyone; she traveled to Puerto Rico to celebrate Hicks’s 41st birthday but was home in time for her own 29th wedding anniversary. (“Engagements must be kept” was her mantra.) Quinn notes press corps whispers but says nothing of what the presidential staff made of the two women. Surely there was an innocent explanation for why the White House seamstress was altering Mrs. Roosevelt’s old dresses for her friend Hick. But who has ever preferred the innocent explanation?

With the war years, Quinn’s account resists her bold subtitle, which uneasily accommodates the two women’s diverging paths and fortunes. Eleanor moves on without Hick, nowhere in sight when, late in life, Eleanor falls for a dashing younger physician. We are left to flinch when she assures him, at 72: “I love you as . . . I have never loved anyone else.” He will marry — in Eleanor’s apartment. She goes on to share a New York townhouse with the newlyweds. Triangles seemed to suit her.

Eleanor shaped Hick’s later decades as much as Hick had shaped her White House years. Ailing and broke, Hick agreed to co-author a book with the former first lady, pleased with her friend’s work if not always with her pace. Eleanor persuaded Helen Keller to meet with Hick, who wrote a best-selling account of her life. Both Eleanor and Hick produced memoirs: Hick’s irreverent, moody pages never found a home. Eleanor’s dutiful, bland account of the White House years met with lavish praise. Mrs. Roosevelt had kept all her engagements. She emerges from these pages a resilient, noble, tireless, hopelessly unromantic and entirely singular first lady, one who balked at playing bridge for money because it seemed improper.