Plot:
This is a case found among the papers of the (fictional) “metaphysical physician” Dr. Martin Hesselius and described by his anonymous assistant.
Sir James Barton has served in the British Navy with distinction for some twenty years, particularly in the American War (American Revolution). In his early 40s now, he returns to Dublin with thoughts of settling down. He becomes engaged to Miss Montague, the niece of a Lady L—. They await the return of Miss Montague’s father from India to formalize things.
One night, on his way home after visiting with Lady L— and Miss Montague, he hears footsteps behind him. It’s late, and the streets are deserted. He looks over his shoulder but sees no one. The footsteps seem to run and stop. The seeming pursuit rattles Barton enough that he calls out. No answer comes.
Barton says nothing to anyone at first, least of all Miss Montague.
Similar incidents follow; Barton hears laughter. One day, he meets a small man in a fur-traveling cap. The man says nothing but looks at him with such vicious malice that Barton’s friends notice he’s taken aback.
Thoughts:
The reader watches Barton’s antagonist circle ever closer. Barton is a materialist and doesn’t believe in the supernatural. These experiences shake his disbelief. He finally seeks counsel from well-intentioned experts—even a clergyman—who tell him in the politest of terms that it’s all in his head. He should get some rest, eat better, and get some exercise.
His questions to a medical doctor reveal that he has something he’d prefer not to remember. It’s not entirely clear to the reader yet. Could lockjaw (tetanus) ever look like death?
The reader feels Barton’s terror and this nameless enemy. Not until the end are an identity and a motive made known, though the reader can make some guesses. The author ratchets up the danger to Barton as the story goes on. The result is not so much righteous anger as sadness.
While things take a while to get going, and the reader has a bit to sit through, I like this sad tale.
Bio: Joseph Sheridan Le Fanu (1814-1873) was an Irish writer of Huguenot descent. His early writings include a group of short stories, initially published anonymously in The Dublin University Magazine in the guise of the literary remains of one (fictional) Father Frances Purcell (The Purcell Papers 1838-1850). These range from the creepy (“Strange Event in the Life of Schalken the Painter”) to the silly (“The Quare Gander”).
Le Fanu’s writings include many ghost stories and supernatural pieces. His works influenced such writers as M. R. James and may have inspired portions of Charlotte Brontë’s Jane Eyre (1847). His vampire tale, “Carmilla” (1872), influenced Bram Stoker’s Dracula. “Carmilla” has been adapted for film several times with varying degrees of success.
In 1858, his wife died after what was described as a fit of hysteria. Le Fanu ceased writing for years and became a recluse, taking to his bed.
This story can be read here:
This story can be listened to here: (1:30:03)
Title: “The Familiar”
Author: J. Sheridan Le Fanu (1814-1873)
First published: This is a minor revision of “The Watcher,” first published in the collection In a Glass Darkly (1851). This version was published in 1872.
Length: novelette
Series: Martin Hesselius
Reviews of Old and New Stories. Mostly Old 
That sounds like a really intriguing story and it makes you curious about what it is. Too bad it is a little bit slow.
Well, it was written 200 years ago, when people had more time to read. No TV or internet.
Yes that is a good point