After the events in Godzilla: Planet of the Monsters, the Aratrum fails to contact Haruo and the rest of the crew after their confrontation with Godzilla. The captain orders that if the drones find no survivors for 48, then Aratrum will withdraw from the Earth. Haruo Sakaki is rescued by a native named Miana and treats his wounds with a strange powder. It belongs to an indigenous tribe called “Houtua,” the surviving descendants of humans.
The Houtua rescues the rest of the remaining crew and stops them from questioning. Miana and her twin sister, Maina, use telepathy to talk to their guests and try to understand the reason why they roamed their lands. After Houtua realizes that the group was looking for Godzila, the twins tell Haruo that their god was destroyed by Godzilla and left an egg behind.
After I understand that Haruo’s group is in war with Godzilla and not with their tribe, they are released, but the twins still accompany them both as supervisors and as guides. They are then attacked by worm-like creatures, but they manage to defend themselves from their attack by means of twins. During the struggle, Galu-Gu realizes that the twin arrows use “nanometal”, a remnant of Mechagodzilla – a famous weapon that was built a long time ago to be used against Godzilla, but which was thought to have disappeared .