That late addition to the Holmes mythos, still to come.

We all know about those things Doyle didn't necessarily write that Sherlock Holmes nonetheless picked up as a part of his mythos over the years. Yet for all the lines, the clothing, the pipe styles, there is one thing that has never really stuck . . . an ongoing character.

Watson, Lestrade, Moriarty, Adler, etc., etc. "The world is big enough for us" apparently is the motto of the Sherlockian mythos. Many another character has appeared alongside Holmes and Watson over the last century, yet none has joined their legend for return visits in latter incarnations. Cameos, homages, maybe, but not as a full-fledged member of the rogue's gallery or Scooby gang.

This thought occurred to me as I considered Ms. Harleen Quinzel, whose first appearance was not all that long ago, yet is now one of the most iconic villains of the Batman universe. Sherlock's been around a lot longer than Batman . . . but then Batman has been the product of many hands for years. His story has been told many times, by many voices.

And while Sherlock Holmes has had his latter storytellers, I think the Victorian era held him back. When Moffat and Gatiss proved so decisively that he could work as a current-day detective, combined with public domain status and the rise of the AU, a Pandora's box of Sherlock possibilities was set loose upon the world. We've seen some seemingly very popular, very powerful additions to the Sherlock Holmes myth in newer interpretations . . . yet we still haven't seen the breakthrough new character who will be seen as just a part of the Sherlock Holmes story a hundred years from now.

Could a Molly Hooper or a Detective Bell make the cut? Are they significant enough to return again in a second incarnation, should all rights be allowed for said return?

Redbeard the dog and Clyde the turtle stand a better chance in my mind, as Sherlock Holmes never had a pet before. But are they really characters?

What sort of friend, lover, or villain would fill a void in the existing Canon? Is there such a void? Does Holmes need a tech guy or gal in the modern day? That additional brother who is so mysterious that he dates Taylor Swift? A villain who better matches him than Moriarty? A lover that actually spends time with him, unlike Irene? (I know, I know . . . if the Mary Russell fans' battle cry was "After 1914, Sherlock Holmes is ours!" we now live in a world where the cry of "After 2010, Sherlock Holmes is John's!" has out-shouted it.)

Basically, somebody out there has to tell us a really good Sherlock Holmes story, one that resonates so perfectly due to a particular new character playing opposite Holmes that we can't let go of that person. Public demand can break down all sorts of barriers should a character come along that we all want to see bad enough in retellings of Holmes's tales thirty, fifty, or a hundred years from now.

I'll be eagerly waiting if that day ever does come, as that character will surely tell us something about Sherlock we never quite realized before that makes perfect sense, as good stories do.

A cat. That's it. Sherlock needs a cat . . . .