The same can be said for “The Disappearance of Shere Hite,” an engrossing portrait of the groundbreaking researcher whose first book, “The Hite Report,” made her an instant sensation when it was published in 1976. Based on surveys of women about their sex lives, the report dealt frankly with such subjects as masturbation, faking orgasms and other supposed taboos. Its biggest blockbuster was the startling fact that most of Hite’s respondents had not experienced nearly as much sexual pleasure from penetration as had been supposed by such sex researchers as Masters and Johnson. With vaginal orgasms relegated to myth and the clitoris given pride of place, Hite became the standard-bearer for a new sexual order. “This is going to lead to real changes in the definition of sex between men and women,” she says in an interview with the trailblazing journalist Betty Rollin. When Rollin asks whether that might be dangerous, Hite looks befuddled. “Equality doesn’t seem dangerous to me,” she says simply.

Little did she know. “The Disappearance of Shere Hite” is fascinating on myriad levels, most obviously in the way it illuminates how Hite transformed herself from a lonely little girl in a repressed household to a dashingly romantic figure on New York’s Upper West Side, where her Pre-Raphaelite beauty allowed her to model while she pursued her academic studies. Her good looks were a double-edged sword, giving her entree but also leading male gatekeepers to dismiss her as just a pretty face. Although “The Hite Report” was a near-instant bestseller, the backlash was brewing, and it came on strong. By the time she wrote about men and later about women and their love lives, critics were ready to pounce on her methodology, her supposed hatred of men, her past nude modeling assignments and her own hyper-glamorous self-presentation. By the time Hite died in 2020, she had self-exiled to Europe, virtually forgotten.

Directed by Nicole Newnham with lots of interviews, gorgeous archival footage and a brilliant voice-over by Dakota Johnson, who reads from Hite’s journals, “The Disappearance of Shere Hite” looks ancient and utterly new at the same time. Watching the media set Hite up just to shoot her down — by having her appear with all-male audiences, for example, or on nearly all-male panels — it’s clear that she was diagnosing phenomena like toxic masculinity and gaslighting decades before such terms became commonplace. By the time she loses it when a limo driver patronizingly calls her “dear,” it’s clear that what her critics saw as ego and hysteria was an understandable reaction to a world that just wasn’t ready for her. As Hite notes in one of her diaries, the constant challenge was to be oneself outside the prescribed expectations of one’s role. “And it’s hellishly hard.”

One of the most bracing elements of “The Disappearance of Shere Hite” is how she found herself within feminism. The heady early days of the movement come to life, not just with galvanizing images but with present-day interviews with the activists, academics, clinicians and assistants who were Hite’s closest friends and colleagues. Newnham reminds us that today’s radical Christian right started its takeover of the Republican Party as a direct result of the movement’s successes. It’s both cheering and depressing to see first ladies Rosalynn Carter, Betty Ford and Lady Bird Johnson attending the 1977 National Women’s Conference in Houston, knowing that such a thing could never happen today.

It’s also a shame that Hite could never fully enjoy the fruits of being so ahead of her time: Today, her focus on sexual freedom and acceptance would make her a feminist and gay rights icon. As regrettable as Hite’s fate was, “The Disappearance of Shere Hite” goes a long way toward rectifying the wrongs done to her, whether in the name of erasure, ridicule or willful misunderstanding. She deserved better, and now she finally has it — even though it’s still hellishly hard.

R. At the Alamo Drafthouse Cinema DC Bryant Street and the Cinema Arts Theatre. Contains sexual material, graphic nudity and some coarse language. 116 minutes.