NEW YORK, NY.- Francine Pascal, a former soap-opera scriptwriter from the New York City borough of Queens who conjured up an entire literary universe among the blue-eyed cheerleaders and square-jawed jocks of suburban Los Angeles, most notably in her long-running and mega-best-selling “Sweet Valley High” series of young-adult novels, died Sunday in Manhattan. She was 92.

Her daughter Laurie Wenk-Pascal said the death, at NewYork-Presbyterian Hospital, was caused by lymphoma.

With covers instantly recognizable by their varsity-style lettering and soft-focus illustrations, “Sweet Valley High” books enraptured a generation of teenage readers with the lives of Elizabeth and Jessica Wakefield, identical twins attending high school in the fictional Los Angeles suburb of Sweet Valley.

The twins are “the most adorable, dazzling 16-year-old girls imaginable,” Pascal told People magazine in 1988. They, and the books, are also strikingly innocent: Even as the thoughtful Elizabeth and the scheming Jessica clash over boys, friends and spots on the cheerleading team, drugs, alcohol and sex barely permeate the 181 titles in “Sweet Valley High,” or the scores of others in the spinoffs — and the spinoffs of spinoffs — from the series.

Within a few years of its debut in 1983, “Sweet Valley High” had taken over the young-adult book market. In January 1986, 18 out of the top 20 books in B. Dalton’s young adult bestseller list were “Sweet Valley High” titles. Taken together, the Sweet Valley universe has sold well over 200 million copies.

That juggernaut revolutionized young-adult publishing. Though there had been no shortage of books for teenage readers — and teenage girls in particular — Pascal recognized their limitless voracity for a compelling narrative and developed a way to feed it.

“There are millions of teenagers that no one in publishing knew existed,” she told The Los Angeles Times in 1986.

Pascal wrote the first 12 books in the series, then worked with a team of writers to keep a steady, rapid publication pace, often a book a month. She would draft a detailed outline, then hand it to a writer to flesh out while relying on what Pascal called her “bible” — a compendium of descriptions of the personalities, settings and dense web of relationships that defined life in Sweet Valley.

“I can’t have any deviation, no matter how small, because it can impact future stories,” she told her daughter Susan Johansson in an email shortly before her death. “The better writers follow my outlines perfectly.”

Pascal had never been to Southern California when the first books appeared, starting with “Double Love,” in which the Wakefield twins fight over the same boy, a basketball star named Todd Wilkins.

That debut also introduced the idyllic Sweet Valley world to readers.

“Everything about it was terrific — the gently rolling hills, the quaint downtown area, and the fantastic white sand beach only fifteen minutes away,” Pascal wrote.

More broadly, those first books acquainted readers from outside Southern California with the Valley Girl aesthetic that would echo through pop culture for decades, shaping speech patterns (uptalking, using “like” as a filler word), clothing and a long list of TV shows, movies and books that are impossible to imagine without Pascal’s influence.

Though she wrote several books before starting the Sweet Valley series, including a nonfiction account of the Patty Hearst trial, Pascal first made her name writing for the 1960s soap opera “The Young Marrieds” with her husband, John Pascal. The TV genre’s influence showed in the contours of the Sweet Valley books, with their convoluted, gossip-fueled story lines, melodramatic plot twists and cliffhanger endings.

Yet she insisted that the books were at heart morality tales, instructing readers on the intricacies of life and illustrating a sense of idealism and wonder that she felt embodied the universal teen experience, whether in urban Queens or sunny Southern California.

“I loved the idea of high school as microcosm of the real world,” Pascal told The Guardian in 2012. “And what I really liked was how it moved things on from Sleeping Beauty-esque romance novels, where the girl had to wait for the hero. This would be girl-driven, very different, I decided — and indeed it is.”

Francine Paula Rubin was born May 13, 1932, in Manhattan to William and Kate (Dunitz) Rubin and grew up in Jamaica, Queens. Her father was an auctioneer.

After studying journalism at New York University, she worked as a freelance writer for gossipy magazines like True Confessions and Modern Screen, and later for outlets like Cosmopolitan and Ladies’ Home Journal.

Her first marriage, to Jerome Offenberg, ended in divorce in 1963. A year later she married John Pascal; he died in 1981.

Both her daughters, Wenk-Pascal and Johansson, are from her first marriage, as was a third, Jamie Stewart, who died in 2008. Francine Pascal, who lived most of her adult life in midtown Manhattan, is also survived by six grandchildren and five great-grandchildren.

She and John Pascal did well as soap-opera scribes, but were not especially taken with the work. When the producers of “The Young Marrieds” insisted that they relocate to Los Angeles, they quit and returned to journalism.

The two went on to collaborate with her brother, Tony-winning playwright Michael Stewart, on the book for “George M!” a critically acclaimed musical about Broadway impresario George M. Cohan.

Francine Pascal wrote her first young-adult novels in the late 1970s, starting with “Hangin’ Out With Cici” (1977), about a girl who travels back in time to meet her mother when she was a teenager. It was made into an afternoon TV special and led to a sequel. Pascal also wrote the young-adult novels “My First Love and Other Disasters” (1979) and “The Hand-Me-Down Kid” (1980).

She was trying her hand at a soap opera treatment, and failing miserably, when an editor friend related a story. The friend had been at lunch when another editor asked why there was no teenage version of “Dallas,” the prime-time soap opera that was among the biggest hits on television at the time.

Pascal ran home and immediately churned out a detailed sketch about twin girls in high school; she sold that, along with her first 12 books, to Random House.

Spinoffs came quickly: “Sweet Valley Twins,” about the Wakefield girls in middle school, began in 1986, followed by “Sweet Valley Kids,” “The Unicorn Club” (a spinoff of “Sweet Valley Twins”), “Sweet Valley Junior High,” “Sweet Valley High: Senior Year” and “Sweet Valley University.”

The “Sweet Valley” series ended in 2003, but restarted in 2011 with “Sweet Valley Confidential,” set 10 years after the action in “Sweet Valley High.”

Pascal also wrote two adult novels, “Save Johanna!” (1981) and “If Wishes Were Horses” (1994), a fictionalized memoir about her life with John Pascal.

In 1999, she began yet another young adult series called “Fearless,” centered on a girl named Gaia Moore who is born without the “fear gene”; she is a crack shot with a rifle and a black belt in karate, skills she uses to fight crime (and, in a spinoff series, in her job as an FBI agent).

Though some critics panned her books’ utopian settings and fanciful plots, Pascal was unapologetic.

“These books have uncovered a whole population of young girls who were never reading,” she told People. “I don’t know that they’re all going to go on to ‘War and Peace,’ but we have created readers out of nonreaders. If they go on to Harlequin romances, so what? They’re going to read.”

This article originally appeared in The New York Times.