The Hounds of Baskerville order to test his theory. He also points out Sherlock was wrong for once; he believed the drug was in Henry's sugar and put it in John's coffee. In the closing scenes, Mycroft oversees the release of Jim Moriarty (Andrew Scott) from a holding cell in which he has written Sherlock's name all over the walls. The story is based on Arthur Conan Doyle's novel "The Hound of the Baskervilles", and also contains plot devices and lines from other Doyle stories: In June 2011, it was announced that Russell Tovey would appear in "Sherlock" series two in its second episode.
The Hound of the Baskervilles of "The Hound of the Baskervilles" led to the character's eventual revival. One of the most famous stories ever written, in 2003, the book was listed as number 128 of 200 on the BBC's The Big Read poll of the UK's "best-loved novel." In 1999, it was listed as the top Holmes novel, with a perfect rating from Sherlockian scholars of 100. Dr. James Mortimer asks Sherlock Holmes for advice following the death of his friend, Sir Charles Baskerville. Sir Charles was found dead on the grounds of his Devonshire estate, Baskerville Hall. Mortimer now fears for Sir Charles's nephew