Caro grew up near Marseille, a coastal city in Southern France. She began writing songs on piano, and later on computer, when she was a teenager. She sang in a shoegaze-influenced band called Dead Sea, who released a few singles followed by 2018's Colorate EP. Eventually, Caro and two of her bandmates, brothers Alexandre and Charles Teiller, moved to London and began making more synth pop-influenced music as Planet 1999. They got in touch with A.G. Cook, founder of influential hyperpop label PC Music, and they soon became the first band signed to the label. Planet 1999 helped co-produce Charli XCX's song "February 2017," as well as the score to Charli's Netflix series I'm with the Band: Nasty Cherry. Their debut EP, Devotion, arrived in March of 2020. Caro's first solo single, "Hide Me Here," appeared later in the year. Several more songs, including "Sad Song 77" and "Heart in 2," appeared throughout 2021, and Caro contributed to Cook's remix album Apple vs. 7G. PC Music released Heartbeats/Heartbreaks, Caro's first album, later in the year. ~ Paul Simpson, Rovi