Hidden from recorded human history, the Kingdom of Spheres once existed on Earth. Its inhabitants, who would now be recognized as people with psychic powers, lived in a society where the gap between social classes widened over time. Greed for power eventually destabilized the kingdom, leading to its collapse. After the kingdom’s destruction, a mysterious girl named Na Yeon was discovered in the Antarctic. Asten, the chairman of the Sphere Union and an ambitious world‑conqueror, sends his followers to monitor her. Na Yeon and her friends must protect three powerful artifacts, keys to world domination, from falling into the hands of the Sphere Union.