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 and sole heir, Sir Henry Baskerville, who is the new master of Baskerville Hall. The death was attributed to a heart attack, but Mortimer is suspicious, because Sir Charles died with an expression of horror on his face, and Mortimer noticed "the footprints of a gigantic hound" about 50 yards from where Sir Charles lay dead. The Baskerville family has supposedly been under a curse since the era of the English Civil War when ancestor Hugo Baskerville allegedly offered his soul to the devil for help in abducting a woman and was reportedly killed by a giant spectral hound. Sir