Occult detective fiction is a subgenre of detective fiction that combines the tropes of the main genre with those of supernatural, fantasy and/or horror fiction. Unlike the traditional detective who investigates murder and other common crimes, the occult detective is employed in cases involving ghosts, demons, curses, magic, vampires, undead, monsters and other supernatural elements. Some occult detectives are portrayed as being psychic or in possession of other paranormal or magical powers.

Joseph Thomas Sheridan Le Fanu was an Irish writer of Gothic tales, mystery novels, and horror fiction. He was a leading ghost story writer of his time, central to the development of the genre in the Victorian era. M. R. James described Le Fanu as "absolutely in the first rank as a writer of ghost stories". Three of his best-known works are the locked-room mystery Uncle Silas, the lesbian vampire novella Carmilla, and the historical novel The House by the Churchyard.