"The marines learn that humanity is of little interest to most of the aliens; the invasion of earth being of little more than a strategic move during a quiet period in an intergalactic war. This war is fought between two opposing schools of literary thought (hyperrealists and deconstructionists) over eleven pieces of prose left behind by the long deceased alien race responsible for building the Gates."

The I-am-not-making-this-up plot to one of the spinoff novels from the original Doom FPS in the 90s.

You thought it was just about shooting demons and bad dudes, but… uh… think again I guess.