E. W. Hornung 
Mr. Justice Raffles [PDF ebook] 

First published in 1909, A Thief in the Night is the first novel detailing the exploits and intrigues of gentleman thief A. J. Raffles in late Victorian England. The novel is a darker work than the three preceding short story collections (The Amateur Cracksman, The Black Mask and A Thief in the Night.) In it a more cynical Raffles finds a corrupt moneylender, Mister Brigstock, is entrapping the young sons of the wealthy with exorbitant interest on his loans, and its up to Raffles to teach him a lesson.