Japan is preparing for Expo '70, to be held in Osaka. Construction of the various buildings and pavilions is well under way. On Wester Island in the Pacific Ocean, a large statue of mysterious origin (called the Devil's Whistle) is located by scientists. The removal of the statue is hampered first by a tribal member of the Wester Island people, then by the unexpected arrival of Gamera, who aggressively attempts to prevent the removal of the statue, only to be shot at by the crew instead. The statue is removed from the island successfully after a volcano erupts. Shortly after departing the island, members of the ship's crew begin to fall ill. The statue appears to be the source of the outbreak, as it makes a continuous piercing sound, driving many of the crew members insane.