London: Headline. 2001.
If you like Stephen Knight, and the conspiracy theory, this one will give you everything: Eddy, Annie Crook, monarchists, anarchists, Gull, Netley, Sickert, an "Inner Circle" and a rather unbelievable Victorian wife who investigates murder. It is a good read, if not to be taken too seriously. If Victorian mystery fiction is what you after, try Perry's Inspector Monk series, and give the Pitt books a miss.