Stephen Fry at The Guardian:
Now, you should know that the Sherlock Holmes body of work written by Arthur Conan Doyle himself is called by Sherlockians “the Canon” (coincidentally and happily an anagram of Conan). The Canon comprises four full-length novels and five collections of short stories.
In all, 60 canonical stories. How many have been written since? I don’t believe it is possible to count. I know I have written one myself. Conan Doyle’s son Adrian Conan Doyle, along with the great Golden Age mystery writer John Dickson Carr, wrote a collection of new stories under the title The Exploits of Sherlock Holmes. After that, the stampede was on, in all media, of course. The Hollywood films starring Basil Rathbone as Holmes and Nigel Bruce as Watson began in 1939 with the canonical The Hound of the Baskervilles, but soon began to move the pair into all kinds of modern settings. By the 1940s, they were doing their bit for the homeland by pitting themselves against the Nazis. The Conan Doyle Estate was open to allowing and authorising such variations, which soon became an established and legitimised part of the whole Sherlock Holmes enterprise. Between 2014 and 2023 Holmes emerged from copyright and entered the public domain.
Most Sherlockians I have come across will, like me, cite Jeremy Brett as their favourite Holmes, but one feels there will always be a new kind of Sherlock for every age.
More here.