Tianyuan Fighter, also known as Musical Wonder 2, tells the story that four young musicians, Xi Yunhu, Dongxing Aolong, Nangongyan and Xuanwu XIII, have grown into little heroes. They show their great power in Tianyun Interstellar. With their wit, kindness, kindness, loyalty, justice and courage, they fight with the evil forces represented by the black bully and influence them with music and songs. In the end, the four became little heroes who benefited mankind and United society.