"Duke Nukem 3D" is set "sometime in the early 21st century", starting in a badly worn down Los Angeles. The game moves on to places such as lunar space stations. An alien transgenic species has invaded Earth while Duke has been fighting in space. Duke crash lands back on Earth and finds most humans are gone. Only a few women remain as slaves for the aliens. America has been turned into a wasteland, and pornography has become the only entertainment.