Ichiro Miki (Tomonori Yazaki) is a highly imaginative but lonely latchkey kid growing up in urban (and at that time, polluted) Kawasaki, Kanagawa. Every day he comes home to his family's empty apartment. His only friends are a toymaker named Shinpei Inami (Eisei Amamoto) and a young girl named Sachiko (Hidemi Ito). Every day after school, Ichiro is tormented by a gang of bullies led by a child named Sanko Gabara (Junichi Ito). To escape his loneliness, Ichiro sleeps and dreams about visiting Monster Island. During his visit, he witnesses Godzilla Son of Godzilla and Ebirah, a giant sea monster. Ichiro is then chased by a rogue Kamacuras and falls into a deep cave, but luckily avoids being caught by Kamacuras. Shortly afterward, Ichiro is rescued from the cave by Minilla. Ichiro quickly learns that Minilla has bully problems too, as he is bullied by a monstrous ogre known as Gabara.