A city lost in the mist, fragments of Mercy Springs, California, have appeared throughout different timelines and worlds, leaving behind one frightening question: what happened to its residents? On a cold Friday night in 1983, scientist Tinson Miller forces the appearance of a Black Door—a terrible anomaly rumored to lead to other realities. With the door trapped in stasis in his basement, Tinson attempts to force it open, crossing thresholds that should not be crossed. In his search for scientific discovery, Tinson unleashes a terrifying creature that threatens to consume Mercy Springs.