Mieko Shiomi (b. 1938) is a pioneering Japanese artist, composer, and performer, known for her lifelong practice that crosses the boundaries between music, visual art, and performance, which has evolved fluidly across cultures, media, and technologies. She co-founded a leading postwar Japanese experimental music collective, Group Ongaku, and later joined Fluxus at the invitation of George Maciunas, which led her to spend a year in New York from 1964–65. This article presents 11 images from an extended interview with Shiomi, conducted by composers Chikako Morishita and Akiko Yamane during their visit to her home in Osaka in January 2020, as part of the filming of the documentary Shadow Piece. In the interview, Shiomi reflects on her childhood, education, career, and family life, and discusses the creation and reception of works such as Endless Box, Mirror Piece, and Spatial Poem. The conversation, originally in Japanese, was translated into English by Kiyo Kamisawa and the author.