In fanfiction there are sub-genres called Crossover and Alternate Universe. The former is where characters from two different fandoms meet – this could be anything from Dr Who meets Supernatural, to Buffy meets Star Trek, to Downton Abbey meets Mad Men. Often these coincide with Alternate Universe fiction, which is fanfic that deviates away from the canon in a major way, be it location, time period (e.g. BBC Sherlock), characters not dying when they did in the canon, that kind of thing. The reason the two often intersect is because to make two fandoms interact, a major plot device has to be changed (though Dr Who is an easy exception since he regularly travels through time/place).
I’ve recently been looking at early Sherlock Holmes pastiches and I came across a rather brilliant one in Tit-Bits (1903) called ‘Burlesque Conversations: Sherlock Holmes and Brigadier Gerard’ This was brilliant because it’s the earliest example of a crossover/AU piece of fiction I have come across, even if the story itself is merely an amusing parody rather than a serious crossover pastiche. Brigadier Gerard, in case you didn’t know, is another creation of Conan Doyle’s. He is the hero of a series of historical short stories based during the Napoleonic Wars: he is vain, a lady’s man, and gallant, getting into all sorts of adventures and scrapes.
‘Burlesque Conversations’ begins with the typical scene at 221B Baker Street, with Sherlock Holmes lounging around; Brigadier Gerard enters as an old man (he must be *very* old considering the Gerard stories are based in the early 1800s, a hundred years before). Holmes deduces Gerard’s journey, much to Gerard’s annoyance, and the two bicker about how Gerard has been ousted from The Strand Magazine in favour of Holmes. Holmes eventually manages to get rid of Gerard from Baker Street by stinking him out with a pellet of Gorgonzola cheese, a memento from a case he is currently working.
This story appeared in Tit-Bits in October 1903. This was after Conan Doyle had officially broken the hiatus and revealed Holmes’ survival of the Reichenbach Falls in ‘The Adventure of the Empty House’. It had been confirmed that Conan Doyle would continue to write tales of Sherlock Holmes, but this meant that the series of Brigadier Gerard stories he had been writing in the mean-time for The Strand stopped. In May 1903 the last Brigadier Gerard story appeared (although, true to ACD’s form, it wasn’t actually and he wrote another one-off in 1910).
This burlesque story is amusing and makes parodic use of the Sherlockian tropes such as Holmes smoking a pipe; his demonstration of deductive skills; his ‘lynx-eyed’ appearance, and more what is more forgiving, Holmes’ playful side – amusing himself with annoying Gerard in his calm manner. I particularly enjoy the pun Gerard makes, saying to Holmes, ‘You cannot astonish Etienne Gerard with your inferential synthesis. Are we not from the same ‘Strand’?’ (The Strand Magazine)