H. P. Lovecraft 
Lurking Fear 

The story is narrated by an unnamed seeker of "strange horrors" who is investigating the massacre of a community of some six dozen backwoods degenerates in an obscure region of the Catskills, a massacre which occurred during a particularly violent electrical storm and seems to have been perpetrated by an unidentified clawed beast. The narrator soon discovers that the most sinister legends of the region centre around the abandoned Martense mansion, and he decides-together with two companions-to spend the night in the big old house. And thus our lengthy, four-part tale begins. (Goodreads)