Context:

Mentioned as a book published a few years before 1914, used as a comparison to describe the spy thriller-like nature of the Black Hand conspiracy and its rituals.

Context:

Mentioned as first appearing as a play in 1903 'and then the book in 1905'; discussed as a key antecedent to superhero stories because of the dual identity concept (masked hero vs. foppish Sir Percy Blakeney)