When an author approaches a pastiche, there should be some consistency in character - right? After all, isn't a pastiche supposed to be a loving tribute, an homage to the original author's work? A pastiche should show that this particular author shows devotion or interest in another character or story, that they have taken the time to craft an entire story's plot to fit that character. That's what a good pastiche should do.
Of course, there is the occasional writer who shows little interest in the character they are carrying on. In that case, they take creative liberties. Sometimes their stories have redeeming qualities, but more often the liberties which are taken outweigh the good. Sure - every writer who is handling a pastiche is taking creative liberties. The very essence of what a pastiche is is a creative liberty. However, when an author's creative liberty swallows the story whole than you have a problem - especially when you are the Sherlockian fanatic that I am.
Every once and a while, you'll come across a story which is really well done. Despite an abundance of liberty taking, the story is handled so well that you cannot help but like it. For instance in both "The House of Silk" by Anthony Horowitz and "Dust and Shadow" by Lyndsay Faye, Sherlock Holmes faces the authority of the law when he becomes embroiled in the villain's deadly scheme. Both stories deal with the detective's public image about to shatter like a mirror and how he must regain the public's trust and solve the case. Plot threads like this are nearly nonexistent in the canon, however they do provide some wonderful character insight. My first thought of Sherlock Holmes is not him deftly breaking out of jail, and yet it becomes quite credible if handled in the right manner. Obvious love for Sir Arthur Conan Doyle's character is displayed throughout these two books and even though a large portion of their plot is devoted to a large creative liberty, it makes sense.
When it comes to creative liberties, there isn't more much liberty taking than in the late Fred Saberhagen's series of books which chronicle the life and death(s) of Count Dracula. You don;t get much further away from Doyle than in "The Holmes-Dracula Files" which portrays Sherlock Holmes and Count Dracula as...cousins. Yes folks you read that right - the man who so denied any existence of the supernatural whatsoever is related to the Prince of Darkness, Master of the Undead, King of the Vampires - Count Dracula. Granted, Saberhagen's book works out well for the first 3/4 or so. It's not until the end when we learn of this strange family bond (plus we get the Giant Rat of Sumatra thrown in for good measure). As a one-off story it might have been tolerable, and then...he wrote the sequel. "Seance for a Vampire" finds Sherlock Holmes and Watson way out of their depth when the detective is kidnapped by vampires.
Again, these two books are tolerable. The style of writing is good and for the most part Sherlock Holmes, Dr. Watson, Mycroft Holmes and even Count Dracula (even though he's presented as a protagonist and not an antagonist) are treated fairly well. I certainly wouldn't be the first person to recommend both of these books to the die-hard Sherlockian, but at least they do have some good things in store. But, we're about to go where no man has gone before and returned alive. We're going to pull back the curtain which conceals the Just Plain Ugly. What we are about to look at is by far the worst pastiche I have ever come across.
The fact that he is romantically interested in Mrs. Hudson is strange enough (Mrs. Hudson is about thirty or so apparently and widowed), but he just does not come across as likable at all. He has very few scenes with Dr. Watson and the dialogue between Professor George Edward Challenger is simply stilted in the extreme. The overall premise is not bad at first glance, but after reading the book I really wanted to distance myself from it as best as possible. It now sits on my shelf, never to be opened again - a sad reminder of what can happen when creative liberty is taken too far.
Well folks, we've come to the end of this tangent. If we can look on the bright side of things, I'd say that on a whole I have encountered more good pastiches than bad ones. While not everyone is qualified to create a pastiche, those who are oftentimes excel magnificently. Maybe when the memory of some of the weaker Sherlockian pastiches have faded from memory, we can look unto a more certain future for the Sherlock Holmes-reading public.