In modern-day New York City, humanity remains blissfully unaware of the dangerous supernatural undercurrents that exist beneath their bustling lives. Across centuries, a secret order of priests has long been protecting the populace from these arcane threats, with the aid of an ageless warlock-hunter known as Kaulder, cursed with immortality by the Queen of Witches as she lay dying by his hand at the climax of the Witch Wars long ago. Bearing the burden of eternal life, Kaulder is the last of his kind, a valiant warrior dedicated to tracking down rogue witches, who use dark magic against humans.

Throughout his time, Kaulder has become a sophisticated hunter, utilizing weapons, arcane knowledge, and detective skills to find his prey. With the assistance of a priest from the Dolan order, he maintains the delicate balance of peace between humans and witches. When his current Dolan mentor unexpectedly dies, Kaulder suspects foul play and his investigation leads him to a young witch with her own turbid past. Together, they uncover a plot to unleash a devastating curse on the city, revealing that the remnants of the Witch Queen's malevolence have survived through the ages, threatening to disrupt the hard-won peace between species and ignite a new war. Kaulder's battle against time and dark magic grows increasingly personal as he faces new trials that test his long-standing resolve and immortality.