The police department of Eugene, Oregon, has just made a grisly discovery: the remains of famous mystery writer Jackson Chadwick. All that's left is a human outline of ash, a lower unattached foot, and a ring with the square and compass insignia of the Freemasons.
Detective James McCullough can't help but be shocked by the crime scene's resemblance to alleged cases of the phenomenon known as spontaneous human combustion. With no leads on the supposed crime, McCullough finds an ally with another investigator, Father Anthony Rispoli, who is looking into a similar case of alleged spontaneous human combustion involving a well-known Chicago professor. They soon realize that both victims were members of the same Seven-Six Order of the Freemason Lodge in New York City.
What they uncover is nothing short of chilling. The lodge was engaged in macabre rituals and bloodletting contracts with the devil himself. With two members dead under such strange circumstances, is the devil coming back to collect? And will the lodge's remaining four members be next? Rispoli and McCullough must race against time to save not only the men's lives, but their very souls.