Following a devastating atomic war between USA and Soviet Union, the Earth has plunged into chaos and destruction in the 1990s. It was not until the middle of the 21th century that humanity started to recover from its losses. Earth was nearly abandoned, and representative of the most powerful countries concentrated on space colonization projects. The Americans founded an organization called NSCA (National Space Colonized Association). Their project, SC (Space Colony), was a huge tower, comparable to the mythical Tower of Babel. This is also the home of the game's protagonist, who returns after prolonged space travels, and soon becomes involved in a complex struggle between countries and political organizations.

[from MobyGames]