Yvette Mimieux, who starred as a delicate, vulnerable ingenue in early 1960s movies such as “The Time Machine,” “Where the Boys Are” and “Light in the Piazza,” and who later sought to break out of typecasting by creating her own roles as a TV writer and producer, died Jan. 17 at her home in the Bel Air section of Los Angeles. She was 80.

Michelle Bega, a family spokeswoman, confirmed the death but did not cite a cause.

Yvette Mimieux appears at the premier of “Dead Men Don’t Wear Plaid” in Los Angeles on May 9, 1982. Associated Press/Doug Pizac

A slender leading lady with blond hair and blue eyes, Mimieux was initially known for playing beautiful but passive young women – submissive daughters, students, girlfriends and wives whose lives were shaped primarily by their mothers or romantic partners. “She seems to be the embodiment of fragile femininity,” Family Weekly declared in 1968.

Yet off-screen, “nothing could be further from the truth,” the magazine continued, describing Mimieux as “a loner, a truly rugged individualist” who possessed “the stamina and energy of an athlete.” Her interests extended to ballet, chess, painting, literature, motorcycles, aviation and archaeology, which she studied at the University of California at Los Angeles before going on digs to Indonesia, among other places.

“I suppose I had a soulful quality,” Mimieux told The Washington Post in a rare interview, looking back on the early years of her career. “I was often cast as a wounded person, the ‘sensitive’ role.”

She was 18 when she rose to prominence in “The Time Machine” (1960), the first Hollywood adaptation of H.G. Wells’s classic science-fiction novel. Directed by George Pal, the film won the Academy Award for best special effects and starred Rod Taylor as a Victorian time-traveler and Mimieux as his love interest, Weena. Her character lives thousands of years in the future, at a time when humanity’s descendants have evolved into two groups: the hairy, cave-dwelling Morlocks and the timid Eloi, who look “like a race of blond surfers,” as Mimieux later put it.

The film received warm reviews and, later that year, Mimieux played a Florida-bound spring breaker in the teen comedy “Where the Boys Are,” which explored young people’s changing attitudes toward sex and inspired a slew of beach-party imitators, as well as a 1984 sequel. Her character was part of an unexpectedly brutal date-rape subplot, in which she wanders – traumatized – from a motel room down to a busy road, where she is sideswiped by a car and winds up in the hospital.

Hailed by Life magazine as a “warmly wistful starlet,” she found herself in high demand at Metro-Goldwyn-Mayer studios, which put her under long-term contract. She appeared in four movies in 1962 alone, including “Diamond Head,” as the sister of a Hawaii land baron played by Charlton Heston, and “Light in the Piazza,” an Elizabeth Spencer adaptation in which she played Olivia de Havilland’s intellectually disabled daughter.

Reviewing “Piazza” for the New York Times, Bosley Crowther wrote that Mimieux acted “with sunshine radiance and rapturous grace” but was unable to redeem a mess of a film, in part because her character seemed “no more and no less intelligent than any standard romantic miss in a Hollywood film.”

Mimieux seemed to agree with that assessment. She often lamented the lack of complex film roles for women, telling the Los Angeles Times, “There’s nothing to play. They’re either sex objects or vanilla pudding.”

She generally found richer material on television, starring as a criminologist in “The Most Deadly Game,” a short-lived series from producer Aaron Spelling, and as a thriving department-store executive in “Berrenger’s,” an NBC soap opera. In 1964, she played a surfer who has seizures and charms Richard Chamberlain in a celebrated two-part episode of “Dr. Kildare.” Some viewers were scandalized when Mimieux appeared on-screen wearing a two-piece bathing suit that revealed her navel.

“On television at that time, no one had ever seen a navel,” she later told the Detroit Free Press. “I don’t think the country knew we had them. And then they ran it on the cover of Life magazine. Well, there were all these letters from outraged parents saying, ‘We’re canceling our subscription; how can we put this on our coffee table and show it to our children?’ ”

A decade later, Mimieux wrote and starred in the ABC movie “Hit Lady” (1974), playing a coldblooded contract killer, a stark departure from her earlier film roles. She later co-produced and co-wrote the story for the CBS movie “Obsessive Love” (1984), playing a deranged soap-opera fan who attempts to insinuate herself into the life of her favorite actor. The character was loosely modeled after the would-be assassin of President Ronald Reagan, John Hinckley Jr.

“The network felt people wouldn’t believe me as this woman,” she told the New York Times. “They said to me, ‘She’s a loner, and she shouldn’t be attractive.’ I asked them, ‘Are you saying that only unattractive people can be crazy or lonely or have unfulfilled lives?’ ”

Mimieux won the argument and also pushed back against the network’s desire to make the movie more of a psychological case study, with a precise explanation for the main character’s mania. Instead, she preferred “simply looking at the character, following her, seeing her intensity.”

“In life we don’t always understand everything,” she explained. “Even an analyst may not understand the person after years of analysis.”

Yvette Carmen Mimieux was born in Los Angeles on Jan. 8, 1942. Her mother was Mexican, and her father was French; he worked as an extra in Hollywood movies before trading show business for a job at an electronics firm. Mimieux went to school for a year in Mexico City but was otherwise educated in Hollywood, where she modeled and was discovered around age 15 by publicist Jim Byron, who had previously promoted Jayne Mansfield.

Gossip columnist Hedda Hopper later reported that Byron was flying in a helicopter when he got caught in a downdraft, forcing him to land on a bridle path where Mimieux was horseback riding. Impressed by her beauty, he gave her a business card. “If you’d like to be in pictures,” he said, “give me a call.”

Mimieux debuted as a bikini-clad student in “Platinum High School” (1960), starring Mickey Rooney as a father investigating the death of his son. The movie resulted in her first of three Golden Globe nominations, for most promising female newcomer.

She later starred as Dean Martin’s wife in “Toys in the Attic” (1963), adapted from a hit play by Lillian Hellman; played a young newlywed confronting financial problems and sexual insecurities in “Joy in the Morning” (1965); and appeared as an outlaw’s companion in “The Reward” (1965), a western with Max von Sydow.

Mimieux later starred in the adventure movies “Dark of the Sun” (1968), “The Neptune Factor” (1973) and Disney’s “The Black Hole” (1979). She also acted in two successful low-budget films, the sex comedy “Three in the Attic” (1968) and the crime thriller “Jackson County Jail” (1976), as a wrongly accused woman who kills the police officer who rapes her. New York Times movie critic Vincent Canby praised her “excellent” performance “in a role that subjects her to as many bruises, humiliations and indignities as she might get in the boxing ring.”

Her first marriage, to Evan Harland Engber, ended in divorce, as did her 13-year marriage to Stanley Donen, the director of Hollywood musicals such as “Singin’ in the Rain.” In 1986, she married corporate housing magnate Howard F. Ruby, the founder of Oakwood Worldwide. He survives her, as do a brother, a sister and five stepchildren.

Mimieux last appeared on-screen in “Lady Boss,” a 1992 miniseries, and stayed out of the spotlight in recent years. She had spent decades trying to maintain her privacy, keeping her first marriage secret for two years before it was revealed by the Associated Press.

“I didn’t want to have a totally public life,” she told The Post in 1979. “When the fan magazines started wanting to take pictures of me making sandwiches for my husband, I said no. You know there are tribes in Africa who believe that a camera steals a little part of your soul, and in a way I think that’s true about living your private life in public. It takes something away from your relationships, it cheapens them.”