Sherlock and John investigate the mystery of Sherlock's missing sibling, and the trail leads to Sherringford.
Sherlock is drawn into the case of Culverton Smith after the man's daughter claims that he wiped her memory after confessing that he was a serial killer. Meanwhile, both Sherlock and John deal with their grief in the aftermath of Mary's death.moreless
While waiting for Moriarty to make good on his threat from beyond the grave, Sherlock distracts himself with cases. He stumbles upon one that he believes is connected to his nemesis.
Sherlock must deal with Charles Augustus Magnussen, the most detestable of all criminals: a blackmailer.
Moriarty embarks upon what may be the crime of the century, but breaking into H.M.P. Pentonville, the Tower of London, and the Bank of England is only the start. Sherlock must discover what his greatest foe is up to and stop him, but his reputation, and even his life, come under threat.moreless
Henry Knight claims that his father was killed by a monstrous creature at large in Dartmoor, and asks Sherlock for help. When he and John Watson arrive on the moors to investigate, they discover a top-secret army base may be connected to the death.moreless
The monarchy is threatened by the emergence of compromising photographs. Sherlock is soon on the case, and uncovers links with international terrorism and corruption in the British government. But to avert a royal scandal he must best Irene Adler, a woman every bit as brilliant as he is.moreless
Claire wakes up from sedation to find her children have been taken away from her, before Sophia reveals the devastating truth about Tom's involvement with Dr. Jekyll and Mr. Hyde. Meanwhile, renowned mercenary Carver is offered an unlimited sum to capture Jackman's malevolent alter ego.moreless
When Hyde is released from the box, it appears Jackman is gone forever. However, flashbacks to the original Jekyll and Hyde reveal the importance of Claire Jackman to both present-day Jackman/Jekyll and Hyde. Meanwhile, Hyde asks the institute for a half hour alone with Claire and her children in return for his cooperation so that he can "play."moreless
Tom has been locked into a mysterious box by the organization hunting him and his wife. Claire finds out the motivation of the organization from Peter.
Flashbacks show how Tom and Claire met, the birth of their children and the first manifestations of Hyde.
The wall between Tom and Hyde gets thinner and thinner and trying to suppress Hyde starts to affect the environment. Tom learns about the motivation of the organization hunting him and Peter's part in the whole game. The involvement of Tom's wife Claire makes things a bit more complicated.moreless
Katherine drugs her employer after Tom takes it upon himself to discover the facts about Mr. Hyde's personal life. The separation between Tom and Hyde gets weaker after an incident at the zoo. More secrets about Tom are revealed, when he meets a person connected to his past.moreless
The last living descendant of Dr. Jekyll and Mr. Hyde is Tom Jackman. From time to time his alter ego Hyde wakes. Tom's wife hires a private investigator to find out why Tom left his family life six months previous.moreless
Jeff explains to the guys about 'The Giggle Loop'. Jane's aunt has died, and she wants Steve to come to the funeral pretending to be her boyfriend. Susan invites herself, and so Patrick must come as her 'boyfriend', and all six end up going.moreless