Blackwater Nights by Michael M. Hughes

When Ray Simon receives a desperate call from his childhood friend Kevin, begging him to come visit, Ray can’t say no. Kevin promises to clue him in on shocking discoveries he has made about weird, half-forgotten events in their past—events associated with a summer camp near Kevin’s home in the small town of Blackwater, West Virginia.
 
But when Ray arrives, Kevin is nowhere to be found. So Ray does some investigating of his own, only to find that no records exist of the camp. Yet he is not alone in looking for information. There are Lily, a beautiful redhead with uncanny seductive powers; Crawford, a wealthy collector of art and people; and Micah, the mysterious leader of the Church of the Open Door. All of them are seeking information about the rumored camp. And they are all interested--very interested—in Ray.
 
Then a midnight encounter with strange floating lights sparks a return of old memories—vivid but fractured images that haunt Ray’s waking hours with intimations of terror and cruelty. Something dreadful happened at that camp long ago. Something was awakened there. Now, with the help of his new friend Ellen, a waitress at the local diner, Ray must navigate a path through madness and murder—a path that leads inexorably to an all-but-forgotten night in his childhood . . . and to a future of unimaginable horror.