The Great God Pan (1890) by Arthur Machen

   The Great God Pan is easily Arthur Machen's most famous story. It shocked and fascinated the readers of his time and it has continued to horrify since. Small wonder that it is one of the most anthologized horror stories ever written. "No one could begin to describe the cumulative suspense and ultimate horror with which every paragraph abounds..," wrote H. P. Lovecraft, and he should know. In it Machen created the mysterious Helen Vaughan, one of the most memorable characters in horror ( being a Vaughan of Welsh descent myself, I like to think she was a relation...it would explain a few things). Even though she is kept ever in the shadows of the story, Machen infuses her with the taint of cosmic evil.
   The tale begins with a sociopath scientist who conducts a brain operation on a poor girl who has the misfortune to be in his charge. Through the operation he hopes that she might gain the ability to see a world beyond our own, one forever hidden from us, limited as we are by our five senses. As he puts it, she will see the god Pan. Sadly for her, she does. The experience drives her insane.
   Years later an odd little girl named Helen Vaughan is placed to board with a family in the Welsh countryside. She spends every day wandering through the woods and being generally creepy. Soon a young boy is driven insane when he sees her frolicking in the grass with...something. Later, a young girl is also driven mad after going into the woods with Helen.
   Many years after this a young woman of exotic beauty appears in society (guess who) and drives her poor husband mad. She has ruined him "body and soul." Not satisfied with destroying her husband, Helen takes on a new identity and causes an epidemic of suicide among the men of her acquaintance. Eventually she is confronted by one of the tale's protagonists and he attempts to get her to commit suicide herself. The story contains one of the most ghastly and grotesque endings in all of Machen's fiction.
   Of course, the relationship between Helen Vaughan and the unfortunate victim of the experiment is not long in doubt. As far as how Helen corrupts all those men and drives them to suicide, Machen only hints. Illicit sex is certainly implied to be a big part of it and was one of the reasons his readers were so shocked.
   What Machen would view to be unnatural sex is certainly a constant theme of the story. Interestingly, a horror of the power of nature is also a major part of the tale. Unlike Algernon Blackwood, who held nature in awe and reverence, the religious conservative Machen shows a great distrust of the natural world. He seems to have found it beautiful, fascinating and not to be trifled with. For him we are only protected from the dangers of nature by the strict, repressive rules of society.
   A streak of misogyny is also ever present in the story. The girl who is experimented upon is nothing more than a tool for the doctor. He rescued her from poverty so he considers her his property. And of course Helen Vaughan is responsible for corrupting all those poor defenseless men. I sense a fear of strong, independent women in this story.
   Regardless, this is a masterpiece of horror. Machen was an extremely talented writer and he builds the horror brilliantly in this story. It truly is one of the greatest horror tales ever written. If you have not read it, do yourself a favor and hunt it down. It is in many horror anthologies, including Modern Library's Great Tales of Terror and the Supernatural. It is also available as a free ebook.