PFH #15 - Progeny of the Adder by Leslie H. Whitten

Trade Paperback.  Intro by Will Errickson.

Homicide detective Harry Picard had seen a lot of violent deaths ... but never like this. Three bodies -- blonde, female, strangely emaciated -- were found in the Potomac River with their throats brutally slashed. Each had been seen in the company of a huge, hulking man dressed in black. Picard's investigation catapulted him into a roiling morass of passion, sexual intrigue, violence, and primordial fear ... as he faced an enemy as powerful, and as horrifying, as man's oldest superstitions!