Stagg created the fictional sleuth Thornley Colton, known as
Problemist, the genre's first blind detective living in
New York City in the early 20th century. The independently wealthy Colton relies on his intelligence and superb senses, honed due to his
blindness, and takes only the most difficult cases for the sheer pleasure of solving mysteries, often clashing with the
NYPD along the way. The Problemist series includes 8 short stories and the novel
Silver Sandals (New York :
W. J. Watt & Company, 1916). The short stories were published in
Thornley Colton, Blind Reader of Hearts (London: Simpkin, Marshall, Hamilton, Kent & Company: 1915.) Stagg also authored the novel
High Speed (New York : W. J. Watt & Company, 1916.) Stagg was employed by a newspaper in Newark, New Jersey, wrote numerous short stories and magazine articles, and later became a
screenwriter of 'photoplays' during Hollywood's early era. ==Career as a screenwriter==