Like most films of the prototype days it is short and has no real plot, it's simply an excuse to play around with a few camera tricks in the Melies style. The first Holmes appearance was in 1900 in a one minute vignette called "Sherlock Holmes Baffled". By 1901 a rival London parody was playing entitled "Sheerluck Jones" starring one Clarence Blackiston which also ran for years.
Oddly both London versions featured Charlie Chaplin's first stage credit, as one of the Baker Street Irregulars in starting in 1905, the young Chaplin would also work with Saintsbury and later give much credit to both men for teaching him about acting. By 1903 another London version was opened with British actor Harry Saintsbury. In 1898 Gillete's version was a smash hit on Broadway and touring to London. It was also Gillette who incorporated the iconic deerstalker cap, matching cloak and calabash pipe as stage props to flesh out the role. It was Gillette in fact who wrote the phrase "It's elementary my dear Watson", not Conan Doyle. Conan Doyle eventually had better luck in America with actor William Gillette who rewrote much of the play and incorporated touches not in the original stories. Irving also passed on Dracula which Bram Stoker had written specifically for him so his judgement was not exactly equal to his snobbishness.
These short plays were successful enough for Conan Doyle to decide to write a full dramatic version himself which he shopped around to producers and major stars like Sir Henry Irving and Sir Herbert Beerbohm-Tree, both of whom passed on the play as too trivial for their tastes. Neither of these plays were on-canon nor were they written by Arthur Conan Doyle although he would have had to approve them as he owned the copyright to the character. Sherlock Holmes made his first stage appearance in a London production starring one Charles Brookfield in 1893 and again the following year featuring a John Webb.
At any rate Holmes is certainly in the top three and he's been found in the movies since the early days of silent film.
Sherlock Holmes is often called the most filmed fictional character in history, personally I doubt this is true what about Dracula or Santa Claus? Also Those who say this appear to be listing each episode of each TV or movie series as individual portrayals which is clearly cheating.