In a world ravaged by monstrous parasites that descend from the sky, humanity is pushed to the brink of extinction. Among the chaos, a lone survivor, David—now known as "Deiv"—awakens to a horrifying realization: he is no longer human. Transformed into something neither man nor monster, he wanders a desolate land, torn between his fading humanity and the bloodthirsty instincts of his new form. As he struggles to find purpose, Deiv crosses paths with remnants of human civilization, military factions desperate to fight back, and intelligent parasites who see him as both a threat and a potential ally. His existence is an anomaly—feared by humans, despised by his own kind. Caught in the crossfire between survival and vengeance, Deiv faces brutal battles, impossible choices, and a growing darkness within himself. With intense combat, raw emotion, and a relentlessly grim atmosphere, Parasite Within: The Beginning is a dark and brutal tale of identity, loss, and the thin line between man and monster.