After a shipwreck, a group of survivors stumbles upon the seemingly deserted Infant Island, prompting a scientific exploration. They encounter a hidden tribe and the Shobijin, two miniature twin priestesses devoted to the island's legendary creature, Mothra. Trouble brews when Clark Nelson, a greedy businessman, abducts the fairies for profit. In a dramatic turn, Mothra emerges to save her beloved priestesses, setting the stage for an epic clash between nature and human greed.