Which BBC Sherlock episode adapts Arthur Conan Doyle’s novel The Hound of the Baskervilles?

The BBC Sherlock episode that adapts Arthur Conan Doyle’s The Hound of the Baskervilles is “The Hounds of Baskerville.”

It is the second episode of Sherlock’s second series and was first broadcast in the United Kingdom on 8 January 2012. The story transfers Doyle’s isolated Dartmoor setting into a modern investigation involving a military research base, genetic experimentation and a frightening legend.

Benedict Cumberbatch plays Sherlock Holmes and Martin Freeman plays John Watson in the episode. Russell Tovey appears as Henry Knight, whose childhood memory of a monstrous hound leads Sherlock and John into the case.

The title changes Doyle’s singular “Hound” to the plural “Hounds.” That wording is intentional and helps distinguish the television episode from the original 1902 novel. The episode also uses contemporary technology and neuroscience to reinterpret the source material’s atmosphere of supernatural fear.