The intrigue behind Holmes's missing years.

Patrick Allen as Col. Sebastian
Moran in "The Empty House"
(TV, 1986)

In the Public Domain Review, Andrew Glassard speculates that Sherlock Holmes may have been involved in espionage between "The Final Problem" (1893) and "The Adventure of the Empty House" (1903). He also looks at the backdrop of international intrigue behind "Empty House."