Dana Andrews is a scientist who wants to drill through the Earth's crust to get at the molten rock below, hoping to use it as an energy source for mankind. He is warned by his young assistant, Moore, that such an attempt will cause the earth to crack, but Andrews goes ahead. All goes as
planned until a crack appears, causing disasters around the globe. The scientists explode a nuclear bomb in the path of the ever-growing crack, but the bomb only alters the direction and doubles the speed of the crack, causing a large chunk of the Earth to fly off and create a second moon.
Andrews, dying of cancer and with nothing to lose, lowers a second bomb into the crack, sacrif...