二战结束后不久,日本南海惊现离奇事件,打捞船荣子丸在平静的海面上突然遇难,幸存者寥寥,前去搜救的宾果丸也一去不返。不久,南海附近的岛屿大户岛遭受到恐怖的袭击,岛上的老人声称这便是传说中的怪兽哥斯拉作怪。古生物专家山根京平教授受命前往调查,根据现场遗留的痕迹断定,这个怪物是200万年前侏罗纪时代存活下来的恐龙,并且在原子弹辐射的影响下,化身为更具破坏力的恐怖怪兽。该论断一经公布,便在日本国内引起轩然大波。政客和军队纷纷行动,意欲置哥斯拉于死地。而哥斯拉也闯入东京,进行一场毁灭性的破坏。人类的命运悬于一线…… 本片根据香山滋的科幻小说改编。Japan is thrown into a panic after several ships explode and are sunk. At first, the authorities think its either underwater mines or underwater volcanic activity. The authorities soon head to Odo Island, close to where several of the ships were sunk. One night, something comes onshore and destroys several houses and kills several people. A later expedition to the island led by paleontologist Professor Kyôhei Yamane, his daughter Emiko, and young navy frogman Hideto Ogata (who also happens to be Emiko's lover, even though she is betrothed to Dr. Daisuke Serizawa) soon discover something more devastating than imagined in the form of a 164-foot-tall (50-meter-tall) monster whom the natives call Gojira. Now, the monster begins a rampage that threatens to destroy not only Japan but the rest of the world as well. Can the monster be destroyed before it is too late, and what role will the mysterious Serizawa play in the battle?