The year is 1999--the place, New York City. While investigating a string of unexplained--and otherwise unconnected--cannibalistic killings, detective Lee Mercer of the NYPD discovers to his disbelief that each killer had previously played a pre-released copy of The Nightlands, an occult-themed tabletop role-playing game. Mercer brings an occult specialist named Morgan Freeman Brown onto the case, and Brown, after playing the Nightlands game himself, falls under its eldritch curse. Brown degenerates into violence and unnatural appetites, but he manages to launch a desperate raid on Masters Warehouse, the facility from which countless copies of The Nightlands are about to ship out to comic-book stores across the country. Brown hopes to destroy the games and so spare others from his fate, but his raid fails. By now the target of a massive NYPD manhunt, Brown disappears. New York Mayor Rudy Giuliani, whose nights are consumed in playing his own pre-released copy of The Nightlands, has been watching all this from afar. Cursed and addicted to The Nightlands, Rudy too knows its danger. He hires August Laine, a hacker gigging for a company called Enron, and Beverly Beverly, a Jamaican demon huntress, to succeed where Morgan Freeman Brown failed. August and Beverly, with support from Rudy, succeed in destroying all of the mass-produced copies of The Nightlands before their shipment across the country. Mere days later, however, August is assassinated by a redheaded sorceress commanding a monstrous golem. With Beverly imprisoned for her attack on Masters Warehouse, and Rudy off tracking Lee Mercer in the wilds of Canada, those present at August's death begin investigating its cause, following a trail between Boston and Arkham and ultimately toward the resting place of the fabled Necronomicon.