Persson made her film debut as the lead in Mac Ahlberg's Danish-Swedish erotic film Jeg - en kvinde (1965) which became the surprise box-office hit I, a Woman (1966) for Radley Metzger in the United States. She appeared in the German film Das Rasthaus der grausamen Puppen (1967) and in Mission Stardust (1967), and then Metzger hired Persson for a title character in his 1968 French film Therese and Isabelle about a lesbian sexual affair between two schoolgirls.
Persson's acting career began with a lead role in an erotic film, which was later adapted into a different version in the United States. She then appeared in films that explored themes of sexuality and relationships, including a French film about a lesbian affair between two schoolgirls.