In June 1956, she met Armando Bó on a television show. He later offered her the opportunity to star in "El trueno entre las hojas (Thunder in the Leaves)." Bó convinced Sarli to be naked in a scene in which she bathed in a lake, though she had previously been told she would wear a flesh-colored body stocking. Bó likewise told Sarli they would shoot from afar and that the camera possessed no facility for magnification. The film became the first to feature full frontal nudity in Argentine cinema. She went on to become an international Latin American star and made international headlines for the nude scene. She appeared in "Time," "Life," and "Playboy" magazines, the first Argentinian actress to accomplish that feat. Bó and Sarli became lovers and she became the primary star of his films until his death in 1981. During this time, Sarli refused many offers to work with other directors, with the exception of Leopoldo Torre Nilsson on "" and Dirk DeVilliers on "The Virgin Goddess", her only English language film.