I don't know Arsène Lupin, but I
did just finish reading E.W. Hornung's oeuvre of
A. J. Raffles, a "gentleman thief" predecessor to and inspiration for Lupin, himself heavily modeled on Sherlock Holmes. Hornung was Doyle's brother-in-law, and wrote 26 short stories and one novel vice Doyle's 56 short stories and four novels. While they may lack the iconic and standout elements of the Holmes canon, they didn't get stale, as Doyle's later output did. That said, the lone novel and last-published story "Mr. Justice Raffles" prominently features a regrettable anti-Semitic caricature of a villain. The heroes focus their venom on him only, so one could make the defense that this bad egg of a money-lender just happens to be Jewish, but it still makes one wince, especially given the rest of the book is so strong, but, that's history for one.
Though all Hornung's Raffles stories are in the public domain, and he starred in seven movies before WWII alone, he seems to have been mostly forgotten by non-Holmes fans in recent decades, and there don't seem to have been significant reprints of his adventures, which is a shame, because Hornung's prose is quite equal to Doyle's, and the fact that heroes are thieves gives many of the stories an element of suspense and personal stakes Holmes' adventures sometimes lack. I highly encourage all Holmes fans to check out the stories in order of publication, whether in print or via public domain ebook.
Fun tidbit: in 2009, I personally asked Nicholas "
Wrath of Khan/
The Seven-Per-Cent Solution" Meyer if he might ever write a fourth Holmes pastiche, and he said he hadn't ruled it out, but hadn't thought of a sufficiently tempting hook. He genially dismissed my suggestion of a Raffles crossover as too obvious (besides, it's been done more than once since 1932), and said he thought the authorship behind
The Protocols of the Elders of Zion might be more promising, though he didn't yet have a particular Holmes angle in mind.
