In the distant future, an escaped mental patient (Calvin) finds an opening to a vast underground network of tunnels, caves, and subterranean structures known as "The Catacombs." Injured and fleeing for his life, he has no choice but to enter.
Once underground, his broken mind runs wild. As pursuit by GovCo agents drives him deeper into the Earth, the darkness pushes his fragile mind to its breaking point.
On his journey, he meets numerous bizarre figures. Some are friendly, some are malevolent, and some with motivations he cannot ascertain. With no way if telling who is real, who is not, and who is out to get him, he can only continue to flee.
Eventually, it becomes apparent to Calvin that he is playing a central role in a grand machination with implications that reach around the globe and beyond.