ShipwrecksurvivorsarefoundonBeiruIsland(Infantotô),whichwaspreviouslyusedforatomictests.Theinteriorisamazinglyfreeofradiationeffects,andtheybelievethattheywereprotectedbyaspecialjuicethatwasgiventothembytheisland'sresidents.AjointexpeditionofRolisicanandJapanesescientistsexploresBeiruanddiscoversmanycuriousthings,includingtwowomenonlyonefoot(30centimeters)high.UnscrupulousexpeditionleaderClarkNelsonabductsthewomenandputstheminavaudevilleshow.ButtheirsweetsingingcontainsatelepathiccryforhelptoMothra,agiganticmoththatisworshipedasadeitybytheislandpeople.ThegiantmonsterheedsthecallofthewomenandheadstoTokyo,wreakingdestructioninitspath.