一次大地震令洛杉矶地底深处的火山喷发，向着住宅区流去，维修地下管道的工人被烧死。地质学家艾美和朋友下去隧道勘测时亲身经历了朋友被岩浆喷发带走了生命。一时之间，城市一隅充满了地底爆发的岩浆。危机处理中心总指挥麦克（Tommy Lee Jones 饰）采取了艾美博士的建议开始疏散人群，他们先利用数百万吨空中降水来使来势汹汹的岩浆变成障碍物，阻挡了岩浆的流动。正当大家以为松一口气时，艾美博士认为岩浆并没有真正被阻挡，只是改变了流向，而且正在往充满伤员的医院奔涌。他们只剩下30分钟的时间去处理这个问题，他们能成功吗？
Scott（卡斯帕·凡·迪恩 饰）过去曾是一名消防员，这次他与一群生态学家组成了一支队伍前往一处油井，目的是在那里悬挂写有生态标语的横幅。但是十分不巧的是，他们在错误的时间去了错误的地方，那里居然有一颗在几秒内即将爆炸的定时炸弹！当Scott一行人躲起来之际，炸弹爆炸了，并引起了强烈的火龙卷！火龙卷所到之处无一幸免，全部都被摧毁。原来，这处油井中所含的并不是普通燃料，而是由Synco公司研发的MT-11实验燃料。好不容易逃过一劫，Scott等人又被起诉制造恐怖事件，遭到Synco公司的追捕，他们必须赶在洛杉矶被摧毁之前阻止火龙卷的肆虐。
Set in the 18th century, the show follows the Shogun Yoshimune, who likes to disguise himself as a low-ranking samurai and go into his capital of Edo to see the life of the common man, as well as to seek out and punish evildoers who would hurt his citizens. He is aided by Magistrate Oo'oka and a vivacious fireman, Tatsugoro, as well as a rotating cast of other recurring characters. Along with Zenigata Heiji and Mito Kōmon, it ranks among the longest-running series in the jidaigeki genre. Like so many other jidaigeki, it falls in the category of kanzen-chōaku, loosely, "rewarding good and punishing evil."
