"Science Fiction Saiyuki Starzinger" is a space opera anime that reimagines the classic Chinese novel "Journey to the West" in a futuristic, interstellar setting. The story is set in a distant future where the galaxy is ruled by the Great Planet, a central authority maintaining peace and order. However, the galaxy faces a crisis as the energy source sustaining it, the Cosmo DNA, begins to deteriorate. To prevent catastrophe, the Great Planet's queen, Aurora, embarks on a journey to the Solar Capital to restore the Cosmo DNA. Accompanying her are three cyborg guardians: Kōtarō, Hakka, and Shura.

Kōtarō, the youngest and most human-like of the trio, serves as the primary protagonist. He is impulsive, hot-headed, and often driven by emotion, but his determination and courage make him a key figure in the mission. Hakka, a large, boisterous cyborg with immense strength, provides comic relief and brute force, while Shura, a stoic and disciplined warrior, balances the group with her strategic mind and combat skills. Together, they form a dynamic team tasked with protecting Queen Aurora from various threats as they traverse the galaxy.

The journey is fraught with danger as the group encounters hostile forces, including the Dark Empire, a malevolent faction seeking to exploit the weakening Cosmo DNA for their own gain. The Dark Empire's leader, Azuma, and his subordinates, such as the cunning General Ryū and the enigmatic Princess Fūma, serve as recurring antagonists. Each planet they visit presents unique challenges, often involving battles with powerful enemies or moral dilemmas that test the characters' resolve.

Themes of loyalty, sacrifice, and the struggle between good and evil are central to the narrative. Kōtarō's growth from a reckless youth to a responsible leader is a focal point, as he learns to balance his emotions with the demands of their mission. The series also explores the relationship between humanity and technology, particularly through the cyborg characters, who grapple with their dual identities as both machines and sentient beings.

The plot is episodic in structure, with each episode or arc focusing on a specific planet or conflict, while maintaining an overarching narrative tied to the journey to the Solar Capital. The blend of action, adventure, and science fiction elements creates a compelling and fast-paced story, with moments of humor and drama interspersed throughout. The series concludes with a climactic confrontation that resolves the central conflict, bringing closure to the characters' arcs and the galaxy's fate.