This is Machen's masterpiece. Not a word I use lightly. Machen's descriptive powers are at their height here and his ability to decribe physical and psychological landscapes is nowhere more evident than in this book. The writing builds as the story progresses and the ending is the strongest I have ever read; it makes 'The Turn of the Screw' look like a damp squib. If you never read anything else by this writer, please, read this. If there's any humanity in you at all, it will have you staring at the wall for an hour after you finish it. Really.