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 giving his name as 'Sherlock Holmes' to the cabbie. Holmes, now even more interested in the Baskerville affair but held up with other cases, dispatches Watson to accompany Sir Henry to Baskerville Hall with instructions to send him frequent reports about the house, grounds, and neighbours. Upon arrival at the grand but austere Baskerville estate, Watson and Sir Henry learn that an escaped murderer named Selden is believed to be in the area. Barrymore and his wife, who also works at Baskerville Hall, wish to leave the estate soon. Watson hears a woman crying in the night; it is