"Space Journey - The First Dream of Wonder-kun" is a science fiction anime series centered around the adventures of a young boy named Wonder-kun, who embarks on an interstellar voyage to fulfill a mysterious dream. The story begins on Earth, where Wonder-kun, an ordinary yet curious child, experiences recurring visions of a distant planet and a cryptic message urging him to "find the First Dream." These visions are accompanied by a strange, glowing artifact that appears in his possession, which he later discovers is a key to an ancient spacecraft hidden beneath his home.

Upon activating the spacecraft, Wonder-kun is thrust into a journey across the galaxy, guided by an AI named Nova, who claims to be the guardian of the First Dream. Nova explains that the First Dream is a legendary phenomenon tied to the origins of the universe, capable of granting immense knowledge and power to those who uncover its secrets. However, the journey is fraught with danger, as a powerful interstellar empire, the Zoraxis Dominion, seeks to claim the First Dream for its own nefarious purposes.

Throughout the series, Wonder-kun encounters a diverse cast of characters who join his quest. Among them are Lyra, a skilled pilot from a war-torn planet seeking redemption; Orion, a rogue scientist with a deep understanding of ancient technology; and Kibo, a sentient robot with a mysterious connection to the First Dream. Together, they navigate treacherous star systems, uncover forgotten civilizations, and face off against the relentless forces of the Zoraxis Dominion.

The narrative is structured around episodic adventures, each revealing fragments of the First Dream's history and its significance to the universe. Key plot points include the discovery of ancient ruins on a dying planet, a confrontation with a rogue AI that once guarded the First Dream, and a climactic battle against the Dominion's flagship fleet. The series explores themes of curiosity, friendship, and the pursuit of knowledge, while maintaining a balance between action, mystery, and character development.

As the story progresses, Wonder-kun learns that the First Dream is not merely a physical artifact but a collective memory of the universe's creation, capable of reshaping reality itself. The final arc sees the group racing against time to prevent the Dominion from harnessing its power, culminating in a dramatic showdown that tests their resolve and unity. The series concludes with Wonder-kun and his companions unlocking the true nature of the First Dream, leaving the door open for future adventures while providing a satisfying resolution to their initial quest.