In the near future, a space station dubbed Earth II is built for the purpose of scientific research and world peace. However, that peace is shattered when the Chinese send up a nuclear bomb that is orbiting just a few miles away from the station. Can the crew disarm the bomb before it detonates, not only destroying the station but setting off World War III?

The U.S. has handed over control of its nuclear defense system to the Colossus supercomputer designed by scientist Dr. Charles Forbin. It soon becomes clear, that the now-sentient Colossus is far more intelligent than its creator realized—with the fate of the world hanging in the balance.