Lord John and the Hand of Devils was written by Diana Gabaldon

Diana Gabaldon

Diana J. Gabaldon is an American author of Mexican-American and English ancestry. Gabaldon is the author of the Outlander Series. Her books they contain elements of romantic fiction, historical fiction, mystery, adventure, and science fiction.-Early life and science career:Diana J. Gabaldon was...

 and collects the novellas
Lord John and the Hellfire Club

Lord John and the Hellfire Club (novella)

Lord John and the Hellfire Club is a historical novella written by Diana Gabaldon, a New York Times best-selling author. The story was initially released in audio form only...

, Lord John and the Succubus

Lord John and the Succubus (novella)

Lord John and the Succubus is a short story written by Diana Gabaldon.It was initially published in Legends II, edited by Robert Silverberg , and then collected in 2007 in the volume Lord John and the Hand of Devils....

, and Lord John and the Haunted Soldier

Lord John and the Haunted Soldier (novella)

Lord John and the Haunted Soldier was written by Diana Gabaldon. It was initially published in Germany, but made its English language debut in the Lord John and the Hand of Devils collection. Historically taking place during the Seven Years War, non-fictional historic events and characters...

. While the first two novellas in the collection were published elsewhere first, 'Lord John and the Haunted Soldier' can only be found in this collection so far.

All three stories feature Lord John Grey

Lord John Grey

John William Grey is a recurring secondary character in the Outlander series and the protagonist of his own series, both of which are written by Diana Gabaldon....

 as the protagonist and begin with a plot point that seems to concern the supernatural

Supernatural

The supernatural or is that which is not subject to the laws of nature, or more figuratively, that which is said to exist above and beyond nature...

but is later revealed to be something else.