Tales about John Silence, 'physician extraordinary'. Silence is a doctor who has become very wealthy through unspecified means and now only takes up cases of a very special kind. He has spent years learning about the supernatural and developing spiritual powers. He assists people who face some sort of supernatural crisis - the humour writer who loses his sense of humour after a cannabis trip awakens a slumbering spirit in his house, a businessman who returns to the monastic school of his youth to find that the pious brothers harboured a very dark secret, island campers who are plagued by a lycanthrope and so forth.
These stories are very much influenced by the spiritualism of the late Victorian era and as such offer a strange mix of rationalised explanations of the supernatural and a great deal of credulous fascination with hermetic esoterica.
Blackwood's tales are very well structured, building up a vivid, nightmarish vision of horror through his evocative, vivid language. There is always something original and distinctive in the way the horror in his stories is deployed or combated. A wide variety of settings and characters are vividly brought to life and a number of highly effective supernatural premises explored in gripping, satisfying tales. My favourites are ANCIENT SORCERIES, where Silence is only a peripheral figure, and THE NEMESIS OF FIRE, a particularly effective tale that ends with ancient Egyptian evil being confronted in a mouldy underground cavern in the south of England. But they're all worth reading; just be prepared for a tone and pace of reading that belongs to an era that is almost a century past now.