In the near future, the use of nuclear weapons has destroyed the earth's ozone layer. Harmful ultraviolet rays caused crops to wither, strange diseases to spread among the people, and most of the human race to die.
The few who remained, however, struggled and found a way to survive in this world.
A few years have passed since then. The earth had regained peace, a power that seemed to be 3', but a black shadow was lurking in the background.