After United States-born activist, critic, filmmaker, teacher, and writer Susan Sontag died in 2004 at the age of 71, the New York Review of Books hailed her as “one of the most influential critics of her generation.” But not everyone had regarded her with such admiration. Some LGBTQ people, for instance, expressed disappointment that Sontag had not become a spokesperson or advocate for the community. Meanwhile, conservative theorists at the Heritage Foundation simply wrote her off as “part of the Blame America First crowd.” Similarly, writers at the right-leaning American Spectator labeled Sontag as a “pseudo-intellectual;” after her death, they continued to dub her a “bad” thinker and ideologue.

Throughout her life, Sontag’s work and persona elicited strong reactions such as these. In fact, most of the people interviewed in Nancy Kates’ engrossing biopic, Regarding Susan Sontag, describe her as brash, opinionated, impulsive, narcissistic, brilliant, and bold. She also drove a hard bargain, something she emphasized as keynote speaker at Vassar College’s 2003 graduation. Archival footage shows her telling the assembled students not to “take shit. Tell the bastards off.”

This audacious spirit is beautifully captured in the film, newly released for circulation from Women Make Movies. The film weaves Kates’ film crew’s one-on-one interviews with people close to Sontag—among them, her son David Rieff; sister Judith Sontag Cohen; writers Nadine Gordimer, Stephen Koch, Fran Lebowitz, Sigrid Nunez, Darryl Pinckney; scholars Terry Castle, Wayne Koestenbaum, and Deborah Nelson; film scholar Don Levine; retired women’s studies professor and dean Catharine Stimpson; and lovers Lucinda Childs, Eva Kollisch, Annie Leibovitz, and Harriet Sohmers Zwerling—with footage of Sontag herself. The end result is a showcase for the swagger that was Sontag’s trademark.

Regarding Susan Sontag is the only full-length film thus far to take an in-depth look at the writer-scholar-filmmaker. While most of its 100 minutes focuses on Sontag’s public persona, viewers are given a bare-bones outline of her childhood, adolescence, and early adulthood. This serves to humanize the literary icon, giving a sense of the tremendous drive that made her want to produce lasting arguments and be remembered. We’re told, for example, that Sontag began writing poems, stories, and plays as a 6-year-old, an activity that allowed her to channel her “interest in everything.”

We also discover that her early years included tragedy: Her father, Jack Rosenblatt, a businessperson who worked in China, died of tuberculosis when Sontag was 5 years old. A year later, her mother, Mildred Rosenblatt, moved the family from New York City to Tucson, Arizona, where, Judith Sontag Cohen recalls, they got little maternal attention. “We had a lot of uncles who were not really our uncles,” Cohen told Kates. “Our mom was very glamorous but she was a part-time mother.”

Several years later, Mildred married Nathan Sontag, a U.S. Army captain who gave the girls his surname. Shortly afterwards, the family again relocated, this time settling in Sherman Oaks, California. There, Susan discovered the Pickwick Bookstore: In the film, actress Patricia Clarkson reads from Sontag’s diary, reporting that Sontag bought what she could, “stealing when I dared,” and making books her “household deities.”

In 1948, at age 15, she enrolled at the University of California, Berkeley. Her first female lover, Harriet Sohmers Zwerling, recalls in interviews that she took the teenager into San Francisco’s drag clubs and under-the-radar lesbian bars, introducing her to gay life.

“She was wild,” Zwerling, five years Sontag’s senior, told Kates. “She’d never had any kind of sex.”

At that point, Zwerling said, “Men left [Sontag] cold.” Two years later, however, when Sontag was studying at the University of Chicago, she met professor Philip Rieff. After a ten-day courtship, the pair married; in 1952, when Sontag was 19, she gave birth to her only child, David.

By 1957, Sontag’s discontent with domestic life prompted her to accept a yearlong fellowship to study literature, philosophy, and theology at St. Anne’s College, Oxford University. Once settled in England, Sontag traveled to Paris and rekindled her relationship with Zwerling, who had become an integral part of the city’s expatriate community. David, meanwhile, remained in the United States with his paternal grandparents.

Upon returning to the United States in 1958, Sontag divorced Rieff and began writing in earnest. Her first book, The Benefactor, was published by Farrar, Straus and Giroux (FSG) in 1963 and was subsequently translated into 18 languages. Sontag called it “a philosophical novel.”

The 1960s brought her further glory, especially after she published 1964’s “Notes on Camp” in the Partisan Review. The essay, scholar Nelson told Regarding Susan Sontag’s filmmakers, allowed “gay trash” to come forward for the first time and “claim a position for itself.” The piece also made Sontag something of a celebrity: She was soon publishing in the New York Review of Books, the Atlantic, and elsewhere. Even Andy Warhol, known for taking pictures of luminaries and trend-setters, extensively photographed her. Meanwhile, Sontag had love affairs with then-prominent dancer/choreographer Childs and playwright Maria Irene Fornés.

Feminism also became extremely important to her, although as writer Nunez quipped in the film, “She was a feminist who found most women wanting … She wondered why they spent so much time worrying about their appearance rather than their intellect.”

This acerbic nature extended into Sontag’s personal life as well. Former partner Eva Kollisch told Kates that Sontag was not only impatient, “she was not a sensitive person,” and was frequently dismissive or even rude.

Sontag’s self-image involved duality—she dubbed herself a “genius-schmuck,” something she felt was in-born and consequently beyond her power to change. She nurtured her raging curiosity rather than try to alter this nature, probing topics as disparate as science fiction and horror movies, the Vietnam War and documentary photography.

Her desire to understand world events led her to visit North Vietnam in 1968, and she was an outspoken opponent of United States involvement in that country’s civil war. Several years later, in 1973, she traveled to Israel, releasing a documentary the following year about the Arab-Israeli conflict called Promised Lands. In Regarding Susan Sontag, actor Clarkson provided a voiceover to illuminate Sontag’s reflection on the experience: “The situation is more horrible than any kind of pictures can convey. There is a culture of war. I am generally a supporter of Israel and don’t think this is incompatible with a left-wing point of view.”

At the same time, Sontag was conflicted and wrote, “I feel, as a Jew, a special responsibility to side with the oppressed.” The film does not touch on the way these films or comments were publicly received, but in general, Sontag’s takes on war often garnered controversy on both sides of the political aisle.

Before Sontag could ponder the issue further, however, she had her first brush with mortality. Shortly after returning from Israel, she learned that she had a rare, and extremely aggressive, form of breast cancer. Doctors gave her six months to a year to live—a conclusion that she refused to accept. Instead, she found a French physician who agreed to give her stronger treatment for longer than doctors in the United States recommended. Nicole Stéphane, a romantic partner based in Paris, cared for Sontag throughout the ordeal, which lasted from 1975 to 1976.

Grappling with a potentially terminal illness led to Illness as Metaphor, a 1978 text from FSG that challenged the idea of illness as punishment or something that a person brings on him-or-herself. “Illness is not a metaphor,” she wrote. “There is such a thing as thoroughly un-deserved catastrophe.”

This theme was revisited in the 1980s when Sontag penned AIDS and Its Metaphors, published by FSG in 1989: a look at the intersection of homophobia, stigma, and illness. “People are made to feel ashamed of being ill,” she wrote, offering a direct challenge to the pervasive discrimination that was often directed at people with the virus.

Sontag reveled in writing about AIDS, illness, and other diverse—and often controversial—topics, telling interviewers that she did not want to be thematically limited. “My appetite is voracious, promiscuous,” she said in footage from the film.

She later wrote two more novels, The Volcano Lover in 1992 and In America in 2000, winning the U.S. National Book Award for the latter. In between, she collaborated with Annie Leibovitz on her 1999 book, Women. All told, Sontag wrote six novels, four plays, six collections of essays, and four monographs. She also directed four films.

Sontag angered right-wingers numerous times, including when she traveled to Vietnam; when she called the white race “the cancer of human history” in a 1967 article in Partisan Review; and when she suggested that the September 11 attacks on the World Trade Center and Pentagon were a response to U.S. foreign policy.

Despite loud criticism, she never backed down or recanted her views. Instead, her activism included a stint from 1987 to 1989 as president of the PEN American Center, which works to “advance literature and defend free expression.” Journalist Mark Danner told Kates that this was a direct outgrowth of Sontag’s belief that “writers must take a stand and be on the front lines, stand for something.”

Regarding Susan Sontag honors this conviction and celebrates Sontag without becoming idealistic. Indeed, she is presented as a real person: flawed, of course, but nonetheless compelling and provocative. In this regard, it wonderfully humanizes Sontag, highlighting her many strengths and weaknesses. What’s more, Regarding Susan Sontag gives emotional depth to a woman who is mostly known for scholarship and wit.

Sontag died of leukemia in 2004 and is buried in Paris. As friend and colleague Koch said in the film, “She fought death to the last moment.”

Correction: This piece has been updated to reflect the correct attribution of a quote in the film concerning Sontag’s view of feminism and the profession of Catharine Stimpson.