The flamboyant and fashionable Ning Ning (), the youthful and free-spirited Liu Dan () and the intelligent and sweet Liang (Qi Zhongyang) met by chance in a karaoke bar. * * * Some of them have different personalities and the same interest in music, which makes them become three sisters and form the "Blue Fox" beautiful girl group. Under the guidance of the devil coach Xia Tian (Zhao Chunyang), the "Blue Fox" three sisters are maturing.

Their title song is "Who are you crazy about?"