Immoral Certainty — Robert K. Tanenbaum

First the rituals, then the blood, then He shall come into His power and rule in the name of Lucifer. And woe to any servant who does not bend her knee in homage....

A killer is working the streets of New York City, snuffing out the most innocent of victims with the "immoral certainty" that he'll never pay for his crimes. Even Assistant D.A. Butch Karp and his colleague, Marlene Ciampi, have never encountered such savagery. Three victims so far, three murders bound in one deadly knot.

The number one suspect is a charming sociopath who's only the first link in a twisted human chain. And following that chain will lead Karp and Ciampi into an underworld where the most benign faces hide the most evil souls--and the worst crimes are yet to unfold....