Olivia Newton-John, the British Australian pop singer who dominated the pop charts of the 1970s and ’80s with mega hits “Hopelessly Devoted to You,” “Magic,” and “Physical”—and jolted audiences with her naif-to-naughty turn as Sandy in one of the top-grossing movie musicals of all time, Grease—died Monday at her ranch in Southern California, according to a message on her official Facebook page. Newton-John was fighting stage IV metastatic breast cancer—she’d endured breast cancer on and off since 1992, but it had returned in 2017. She was 73.

“Olivia has been a symbol of triumphs and hope for over 30 years sharing her journey with breast cancer,” the official statement reads. “Her healing inspiration and pioneering experience with plant medicine continues with the Olivia Newton-John Foundation Fund, dedicated to researching plant medicine and cancer.”

Few pop stars can lay claim to Newton-John’s outsize achievements. Her angelic beam matched with a clear, sweet-yet-supple soprano was vocal satin, giving her a versatile edge in singing feel-good numbers across genres and styles. She snagged the longest-running hit of the 1980s with “Physical,” sold over 100 million albums, and throughout her career won four Grammys, landed 10 number one hits, and had more than 15 top 10 singles. 

From the naked vulnerability of hushed ballad “I Honestly Love You” to the risqué-for-its-time sensual synths of “Physical”—which surely gave audiences the first mention of the word horizontally in a pop song as well as an unofficial fitness anthem—Newton-John floated ethereally through a multi-decade, multi-genre career that even upended the movie-musical world. Occasional missteps such as the bizarre Xanadu still bore hits. And she did it all while evoking a demure girlishness mixed with a suggestive sensuality—a modern Doris Day, without all the hang-ups.

Olivia Newton-John was born September 26, 1948, in Cambridge to father Brin, a British intelligence officer, and mother Irene. Her maternal grandfather, Max Born, was a Nobel Prize–winning scientist, quantum physicist, and pal of Albert Einstein’s who fled Germany before World War II. According to the docuseries Intimate Portrait, sister Rona Newton-John, who died in 2013, recalled that Olivia could harmonize effortlessly as a child without any vocal training.

When Newton-John was five years old, her father moved the family to Melbourne, Australia. By 15, Newton-John was singing in an all-girl group, appearing on Australian radio and TV shows, and winning a singing contest whose prize was a trip to London. Encouraged by her mother to stay in London and expand her horizons, she signed with Decca Records in 1966. After a brief stint and commercial flop with a band called Toomorrow, Newton-John released a solo album, If Not for You, in 1971. That album would be her entry to stardom. 

Newton-John’s 1973 album Let Me Be There won her the Grammy for best female country performance and the Academy of Country Music’s honor for most promising female vocalist. She won female vocalist of the year from the Country Music Association in 1974, beating out Dolly Parton and Loretta Lynn—leading prominent artists George Jones and Tammy Wynette to form a separate association in protest. 

Her move to pop balladry with 1974’s “I Honestly Love You” cemented her status worldwide. But it was a dinner party with singer Helen Reddy that would route Newton-John’s radio signals into theaters. There, she met Grease producer Allan Carr—leading to her iconic role as the squeaky clean Sandy Olsson. 

In one of the most memorable movie makeovers of all time, Sandy goes from virgin to vamp with the flick of a cigarette, and a little help from black spandex pants so unforgiving that Newton-John famously had to be stitched into them. With her fresh face traded for a dolled-up, sexually confident woman’s, Sandy brings John Travolta’s Danny—and America—to his knees.

Though the musical was not a win with critics—Pauline Kael notably called it a “klutzburger”—fans were enthralled. Grease became one of the highest-grossing movie musicals of all time, spawning mania, merch, and smash hits “Hopelessly Devoted to You” and “You’re the One That I Want.” The impact of Grease on teen flicks, the musical form, and female sexuality can’t be overstated—and Newton-John and Sandy became nearly inseparable in the public eye.

Her musical career followed that dalliance with role play. Newton-John’s sensuality sparkled in Xanadu, which birthed more chart-topping hits. The mega-hit “Physical” followed and stayed on the charts for 10 weeks, the longest of any single in the ’80s.  

Newton-John married a dancer from Xanadu, Matt Lattanzi, in 1984, and the couple had a daughter, Chloe. They divorced in 1995. During the marriage, she took a break from show business to focus on parenting, and in 1992, was diagnosed with breast cancer. In the intervening years, Newton-John performed and toured on and off, went into remission, and faced a second bout of cancer in 2013. She endured a rare media circus when her boyfriend of nearly a decade, Patrick McDermott, was reported missing, then presumed dead, with reports later emerging that McDermott was alive and had allegedly faked his own death. She married plant medicine entrepreneur John Easterling in 2008, who grows medical marijuana for the singer’s cancer pain management.

She spent her last years focused on health and environmental activism, parenting, and cancer research and awareness. After decades of relative privacy, she released a memoir in 2019, Don’t Stop Believin’. In it, she weighed in on the debate over whether Sandy’s famous transformation was sexist or powerfully liberating. “People forget that he changes for her too,” she told The Washington Post in 2019, reminding us of the Grease scenes in which Danny goes from greaser to jock. “He ends up in a letter sweater when she wears the leather jacket. So they are trying to help please each other—and I don’t think there’s anything wrong with that.”

In the end, she wrote in her book, Grease “was about choice. Wear those pants, or a dress down to the floor. Empowerment comes from calling your own shots and being who you want to be.”