Throughout his adult life, Blackwood was an occasional essayist for various periodicals. During his late thirties, he relocated back to England and started to write stories of the supernatural. He was successful, writing at least ten original collections of short stories and eventually performing by radio and television to tell them.

Of Blackwood S. T. Joshi has stated: "his work is more consistently meritorious than any weird writer's except Dunsany's" and that his short story collection Incredible Adventures (1914) "may be the premier weird collection of this or any other century". One of the most prolific writers of ghost stories in the history of the genre. Blackwood was also a journalist and a broadcasting narrator.