Sherlock Holmes - The Valley of Fear, Part II

That night, outside Birlstone Manor, they witness Barker retrieving the missing American's clothes from the moat. Douglas suddenly appears unharmed, handing Watson a written explanation titled "The Valley of Fear." Douglas reveals encountering his enemy, Ted Baldwin, and surviving a struggle where Baldwin was accidentally shot. With Barker's aid, Douglas staged the scene to mislead his adversaries, hiding in a priest hole afterward.
Douglas, formerly known as Birdy Edwards, shares his backstory as a Pinkerton detective in Chicago, infiltrating a criminal gang in Vermissa Valley. After exposing the gang, Douglas fled to England, fearing retaliation. Holmes advises Douglas to leave England, but Barker later informs Holmes of Douglas's presumed demise at sea. Holmes suspects Moriarty's involvement and vows to pursue justice.

Story from Arthur Conan Doyle, 1901–1902