While driving through the desert with his wife Carol Marvin to a military base to send the eleventh rocket to the orbit of Earth for helping the exploration of the outer space in the Operation Sky Hook, Dr. Russell A. Marvin and Carol see a flying saucer and accidentally records a message in their tape recorder. Once in the base, Dr. Russell is informed by his father-in-law and general that the ten first satellites had mysteriously felt on Earth. When Dr. Russell decodes the message, he encounters the aliens that ask him to schedule a meeting with the leaders of Earth in Washington in 56 days with the intention to invade Earth without panicking the population. Dr. Russell develops an anti-magnetic weapon that becomes that last hope of human race against the hostile aliens.
Dr. Steven Sorenson plans to tap the geothermal energy of the Earth's interior by means of a thermonuclear device detonated deep within the Earth. Despite dire warnings by fellow scientist Ted Rampian, Dr Sorenson proceeds with the experiment after secretly learning that he is terminally ill. This experiment causes a crack to form and grow within the earth's crust, which threatens to split the earth in two if it is not stopped in time.
After a collision with a comet, a nearly 8km wide piece of the asteroid "Orpheus" is heading towards Earth. If it will hit it will cause a incredible catastrophe which will probably extinguish mankind. To stop the meteor NASA wants to use the illegal nuclear weapon satellite "Hercules" but discovers soon that it doesn't have enough fire power. Their only chance to save the world is to join forces with the USSR who have also launched such an illegal satellite. But will both governments agree?
When a shower of massive meteors threatens an extinction level event on Earth, the world's greatest minds devise a dangerous plan that will take the planet off its axis in order to avoid the impact.
