That was my question, up until quite recently, but I have been schoolong myself in Pontine lore.
Pontine, what a great word! Though I must admit, I keep reading it as Poutine.
I have my collections of Mythos Tomes, by various authors (which is by no means complete), and of course my Sherlockian works, but I quite recently discovered the series of tales that could in some ways be seen as the original point of contact of these two universes, the Solar Pons stories.
Solar Pons was a character created by Lovecraft's friend, correspondant, and later publisher through his company Arkham House, August Derleth.
Derleth of course wrote his own, much maligned, mythos tales, but let's not go down that rabbit hole here. Derleth also wanted to write Holmes tales. Indeed he contacted Doyle, to ask if he could take oer the series aftr Doyle had finished with Holmes, but Doyle declined (no doubt Derleth was not the only young author to contact Doyle about this, so I'm not particularly surprised by Doyle's response). So, Derleth went on to create his own Homage to Holmes, Solar Pons.
Pons is very much post modern Holmesian characerture. There are many knowing winks to the audience, sometimes a little heavy handed, but fun none the less. There is the heavy suggestion that Pons was actually trained by Holmes, which the timeline backs up, as these tales are all set in the 1920s and 30s, but in the tales I have read, Homes is not actually named as Pons' teacher. There is much use of the iconography of the films, with deerstalker hats, and copious smoking of nasty pipe-tobacco, and some might say over-use of the word elementary. In one tale, Pons brazenly takes on the alias Proffessor Moriarty of Kings College London.
There is also the interesting crossover witht he Cthulhu Mythos, in that Pons has written a monograph on 'An Examination of the Cthulhu Cult and Others', and may not be quite so closed minded to the supernatural as Holmes was.
I mentioned previously, that I had picked up a copy of Derleth's The Reminiscences of Solar Pons. I had also found the story The Adventure of the Sussex Archers in an anthology I picked up second hand. As stories go, they are fun romps. Derleth captures the character well, and although the mysteries are not always up to Doyle's (mostly) high standard, they are fun. This may in some part be due to the telegraphing of Derleth, which may come from his Lovecraftian studies, as no-one can ever really say they are surprised at how Lovecraft's tales end, except perhaps the protagonists.
London is also well used, despite the fact that Derleth had never been there, although it may be that Derleth's 1920s London pays a little too much hommage to Doyles 1880s London, and may not be all that accurate.
There are also a bunch of Pons tales written by Basil Cooper, but I have yet to track any of these down, so canot comment on their quality.
There seems to be a lack of these tales in current print, possibly due to the lack of knowledge of the character, or maybe the fact he is seen as a pastiche or a rip-off of the original. There may even be copyright issues. Which is why I was surprised to see a Kickstarter for a new anthology of Solar Pons adventures. Of course, I backed it, and am intrigued to see how it compares to the original tales I have read. The fact that this is done in association with Arkham House backs up the copyright theory.
I have previously bought another publication by this publisher, A Study In Terror. I thought I had already reviewed this book here, but it seems not. As a collection of Doyles horror tales, it is a great republishing, but the analysis and other essays were a little amateur. Still, I am slightly annoyed I did not buy the second volume while it was still in print. Maybe there will be a reissue.
This publisher also seems to have a great deal of modern Holmes tales and scholarship available too. If the Pons book is any good, maybe I'll delve into that next.
Either way, once I read through this anthology, I'll be sure to let you, my dear readers, know all about it.
With that, I think that's all I have to pass on for Pons right now, so I will leave you with these other Pontine links of interest:
Solar Pons and Cthulhu, an Essay
Almost Holmes A blog on Pons, Holmes and other books of interest in the same genre.