The Galactic Space Patrol dispatches a single officer to Japan to protect the peace of the green planet, Earth. This officer is Mitsuko Kotsubaki, a woman who lives an ordinary life as an elementary school teacher. But when strange phenomena begin occurring on Earth, she is forced to take up the Moonstone—a powerful gem infused with lunar energy—and fight as Space Woman. The story begins when Dr. Nababa, a villain wanted across the entire universe, appears on Earth and plots to steal the Moonstone. He sets a trap to kidnap members of the Space Patrol, and Space Woman falls into his scheme, captured. Dr. Nababa uses brutal methods to torture her and extract the location of the Moonstone, but she endures the torment, sustained by the voices of her comrades echoing in her heart. Yet her body and mind draw closer to the brink of collapse—can she truly protect Earth to the end?