Shipwreck survivors are found on Beiru Island (Infanto t?), which was previously used for atomic tests. The interior is amazingly free of radiation effects, and they believe that they were protected b...

接續前作“哥吉拉X機械哥吉拉”的故事，一年前與哥吉拉（Godzilla）的決戰，機龍（機械哥吉拉Mechagodzilla）受損程度37%，失去了右腕及終極武器-絕對零度炮。 維修組員中條義人在八王子基地負責修復機龍的工作。某日中條在他叔叔信一的別墅家渡假時，嬰兒島的小美人精靈竟然出現在他們眼前。小美人給他們一個忠告：人類用哥吉拉骸骨製造出機龍是個嚴重的錯誤，如果出動機龍，摩斯拉就會變成人類的敵人...