In the film, a series of earthquakes and forest fires precedes the appearance of a giant robot, Mogera. The mechanical monster wreaks havoc before it is blown up by the self-defence forces. The next day, a gigantic dome emerges from the ground, and we are introduced to the robot's creators: the Mysterians. They beckon key scientists to meet them in their base, where they explain themselves as a race ravaged by atomic war. The Mysterians want three kilometres of land on which to live, but they also have an unpleasant stipulation. The Mysterians' bodies are so damaged by radiation that they can no longer birth healthy offspring; and so, they want to mate with human women. Having already used Mogera to show that conflict is useless, the Mysterians appear to have the upper hand. However, forces from East and West unite, and Earth is poised to take on the Mysterian menace.
It's an interesting time capsule about science, ethics, and politics. Given the renewed possibility of nuclear annihilation, it's worth a read followed by a watch or re-watch of this great, weird movie.
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