Linda Williams, a scholar whose research was foundational to the field of film studies and to feminist film theory, and who wrote extensively about pornography, died on March 12, 2025, at her home in Lafayette, in Northern California. She was 78.

Her husband, Paul Fitzgerald, said the cause was complications of a hemorrhagic stroke she had five years ago.

"Linda was there before there was any such thing as feminist film studies," B. Ruby Rich, the former editor in chief of the journal Film Quarterly, said in an interview. "She played a pivotal role in its development, but she was not orthodox."

Ms. Rich continued: "She did not stay in her lane at a time when people were really guarding boundaries and really policing what others were doing. She was fearless about following her inquiries wherever they would lead. In any branch of academics or scholarship, that is really, really unusual."

A longtime professor of film and media at the University of California, Berkeley, Ms. Williams wrote and edited articles and books on subjects as diverse as surrealism, spectatorship and the television series "The Wire."

She was keenly interested in how various film genres affected the body — for example, the way horror movies could induce shivers — and in her 2002 book, "Playing the Race Card: Melodramas of Black and White From Uncle Tom to O.J. Simpson," she explored how the tropes of melodrama figured in widening and narrowing America's racial divide.

But her most headline-grabbing work focused on pornographic films, which she saw as worthy of consideration as a discrete genre — and worthy of scholarly analysis and inquiry as well. She shrewdly compared pornography to another popular genre: the musical, with song-and-dance numbers swapped out for sexual acts, and with the often laughably flimsy narrative of porn exchanged for, well, the often laughably flimsy narrative of musicals.

Ms. Williams took up the study of pornography in the mid-1980s, when there were huge, noisy fights for and against it in the political sphere.

"But nobody recognized pornography as a genre until Linda came along," Mary Ann Doane, a film scholar and Ms. Williams's colleague at Berkeley, said in an interview. "She was one of the first to write seriously about it, and was met with some skepticism. But her work was so rigorous and so detailed that I think she won people over to the importance of studying porn."

Ms. Williams was at some pains to point out, in print and in person, that she didn't set out to produce an entire book about pornographic films, let alone three such books: "Hard Core: Power, Pleasure, and the 'Frenzy of the Visible'" (1989); "Porn Studies" (2004), an essay collection that she edited; and "Screening Sex" (2008).

"Hard Core," she said in a 1989 interview with The Los Angeles Times, grew out of a book she had planned to write about how the human body had been portrayed in film genres, pornography among them.

"I thought that I could do a quick-and-easy chapter in which all the self-evident truths would be dispensed with rather easily," she said. "I thought, like everyone, if you've seen one porn film you've seen them all."

But what Ms. Williams encountered was a surprising complexity of motive in representing sex onscreen, and a genre that was undergoing a sea change. She became fascinated by the possibilities.

"I discovered that there are so many arguments about pornography and hardly any analyses of it as a form," she said. "And so I decided I would fill that vacuum." She added, "I began to get truly annoyed at the way people presume to pronounce upon pornography without having actually looked at it."

Linda Lorelle Williams was born on Dec. 18, 1946, in San Francisco. She was the elder of two daughters of Lorelle (Miller) Williams, who managed the household and later became a licensed vocational nurse, and Kenneth Williams, a traveling salesman who was on the road during the workweek. Young Linda and her mother took advantage of his absence, staying up late to watch old movies on television. That grounding in the cinema of the 1930s and '40s would serve her well.

She earned a B.A. in comparative literature from Berkeley in 1969 and a Ph.D. from the University of Colorado in 1977; her thesis was on surrealism in film. Before returning to Berkeley in 1997 as a professor in the department of rhetoric and the film studies program (now the department of film and media), Ms. Williams taught at the University of Illinois Chicago and the University of California, Irvine.

Several years after the publication of "Hard Core," she taught her first pornography course at Irvine. Though cognizant of the risks of bringing such controversial subject matter into the academy, she told the University of California newsletter The Berkeleyan in 2004, "I wanted to integrate my scholarship and teaching."

Still, "to label Linda Williams merely as the pre-eminent scholar of sexuality in cinema is to grossly understate her impact," Steven Mintz, a professor of history at the University of Texas at Austin and an editor of the book "Hollywood's America: Understanding History Through Film," (2016), said in an email message. "While she wrote incisive analyses of pornography, her greatest contribution was unraveling the complex interplay between visual representation and human subjectivity.

"No one has written more perceptively about how viewers engage with film as active participants and forge their own identities in the process."

In addition to her husband, Ms. Williams is survived by their son, Quinn.

Early in her teaching career, Ms. Williams wrote out meticulous lectures to present to her classes. One day, she inadvertently left home without her carefully prepared script and had to stand and deliver from memory.

"It went really well, because she was able to engage with the students more directly in discussions of the material," a Berkeley colleague, Kristen Whissel, said in an email message. From that point on, Ms. Whissel said, "She would write up lecture notes, memorize them and leave them in her office."

Obituary written by Joanne Kaufman, The New York Times. Copied on April 4, 2025.