I started writing the story that “Rough Beast” works as an epilogue to when I was working on my Tales from the Aletheian Society anthology submission. About ten lines in I knew it was going to be far too much work, and shelved it in favour of the Petheram Hall tale I ended up with.
Many of the major beats of that story still exist in this epilogue, and one day I may get round to writing it. It's pretty obviously a pastiche of an adventure experienced by an entirely different Victorian detective, but as it might have happened if well-meaning but quarrelsome investigators from the Aletheian Society had been involved.
I'm a big fan of the Society and its world. It doesn't take Victorian Britain too seriously, and gives plenty of scope for messing around with sacred cows (my first pitch for the anthology was a retelling of Dracula with some serious gender swapping because of course it was). Plus I can add as many tentacles as I like, which always makes me happy.
As to the audio... Bill Thomas asked if he could record it along with some of my other stories over the New Year, and I was blown away by the result and also well-chuffed when the Aletheian Society offered to post my glorified fan fiction on their feed.
I'm not done with the Aletheian Society. While Professor Champion is probably off to explore the lost worlds of South America, Mrs Fletcher and Alex at least are likely to turn up again in future stories. I might even get round to writing “The Aletheian Society and the Mystery of the Black Dog” some day. Maybe for the next anthology.