The Sherlockian by Graham Moore

It's far too easy to stereotype an avid fan of Sherlock Holmes, Arthur Conan Doyle's storied and much-beloved detective. After all, the pipe-smoking deductive genius, since his birth in the pages of Strand magazine in 1887, has inspired many admirers to emulate his speech patterns and style of dress. Attend the annual meeting of the Baker Street Irregulars and the demographic will likely skew toward those with more gray than any other color in their hair.
Doing so, however, neglects some facts that surprise at first and seem obvious in hindsight: Sherlockians start on their journey toward admiration of the detective and his sidekick, Watson, at an early age, and much of the best literature that reimagines Holmes in new adventures has been written by authors still in their 20s. They have the energy and enthusiasm to go where countless writers have gone before and, in that state of freshness, stretch Conan Doyle's original world well beyond initial constraints without sacrificing the essence of what makes Holmes and Watson tick.
Graham Moore fits the youthful bill, but his venture into the world that Conan Doyle created is from a series of side angles, not head-on. The novel "The Sherlockian," rather than delving into another Holmes story, turns him into the objet d'art of the Baker Street Irregulars and their ilk. That most certainly includes its youngest member, Harold White, a freelance literary researcher based in Los Angeles prone to wearing a plaid deerstalker hat he had owned "since he was fourteen years old, since he had first become obsessed with Sherlock Holmes and dressed as the famed detective for Halloween."
White doesn't have long to revel in his anointed newbie status, what with the unexpected and gruesome death of Alex Cale, a leading Sherlock scholar who claimed that he'd found a long-missing Conan Doyle diary, a veritable holy grail for the Irregular community. With the proverbial game afoot to find out who killed Cale and find the diary — and what it contained — Moore mixes his entertaining contemporary tale with a parallel one of Conan Doyle's in 1893, just after he'd sent Holmes over the Reichenbach Falls