He is an American treasure hunter in early-twentieth century Afghanistan disguised as a Kurdish merchant, "Ali el Ghazi".
However, O'Donnell seeks hidden treasures in all of his stories while El Borak is more concerned with his own form of justice and stability in Afghanistan.
O'Donnell carries a set of distinctive weapons, a scimitar with a bronze hawk-head on the pommel and a "kindhjal" [sic].
The third O'Donnell story, originally titled The Trail of the Bloodstained God, was not published within Howard's lifetime.
[2] In this story, O'Donnell is in pursuit of thieves who have stolen from him a treasure map that points the way to the precious idol called The Bloodstained God.