Karen, a young psychiatric nurse, boards the last subway train of the night only to have it stop in the middle of the tunnel. Suddenly, her nightmare begins: a mysterious cult has decided that it's the end of the world and the only way to save the souls of the living is to kill them in cold blood. As those around her are brutally murdered, Karen and a handful of survivors must face the homicidal cult, supernatural forces, and their own fears of Armageddon in order to survive.