From the introduction:
You belong to a cell of paranormal investigators. You have glimpsed unspeakable things that live in the darkness beyond the light of human understanding, and yet you still dare to seek them out - to warn others and perhaps contain or banish them if it is within your capabilities.
Walter Blackthorne, leader of the Esoteric Order of Nameless Sensitives (EONS), has just been found dead - in a locked room and ravaged as if by a wild beast!
You and your fellow EONS are stunned, and wondering who may be next!