Earth has been overrun by demons, wiping out 60% of the planet's population. The Doom Slayer returns with a satellite fortress to end the invasion by hunting down three Hell Priests who serve the Khan Maykr, an angelic being willing to sacrifice humanity for her own race's survival. As the Slayer eliminates the priests one by one, he uncovers a deeper conflict between Heaven, Hell, and an ancient pact that has fed on human souls for eons.