In the year 2401, while on an outing, the young boy Dilo, along with Yaoyao and Xiao An, discovers a mysterious object from the core of the Milky Way called the Galaxy Star. The Galaxy Star holds an unsolved mystery of the universe, and the curious Dilo decides to embark on a cosmic journey with his two good friends to unravel this ultimate secret. With the help of the spaceship pilot Lily, they begin exploring the nine planets of the solar system. Aided by the Cosmic Star Gods and relying on their own courage and wisdom, they finally uncover the unknown mystery of the Galaxy Star.