Caught in the Net

A young man of good family is told he is not his father's son but a foundling, and that a document proving otherwise can be bought - for a price that ruins everyone who touches it. Gaboriau was a cavalry trooper and a lawyer's clerk before he invented Monsieur Lecoq and, with him, the detective novel in France; Conan Doyle read him carefully and then had Holmes sneer at Lecoq, which is its own kin...