洛杉矶又受到怪物的袭击，这次袭击的怪物力量远比它们的前辈更为强大，整座城市陷入了恐慌之中，罗素博士临危受死,带领着冲锋队奋起迎战。

Scientists make a horrible discovery: The "Big One" is coming in two days, with it, California will sink to the ocean. Their only hope is to rupture a volcano that will displace the earthquake's energy and build a new crust on the surface. But as foreshocks turn California into chaos, it's a race against time the scientists might not win.