The Adventure of the Greek Interpreter a female pupil of Beeton School who can communicate with animals is kidnapped. She is made to interpret dog's language to find a bone of Neanderthal stolen from a laboratory and taken away by a dog but no clue is found. Holmes decides to solve the case with the help of his elder brother Mycroft and visits him in the Diogenes Club in Dealer house where he lives. Though Holmes is estranged from Mycroft, the brothers and Watson discover the bone and find out that it's Wilson Kemp, a pupil who lives in Dealer house stole it but Mycroft tries
Minor Sherlock Holmes characters their relationship. She also posed as John Watson's therapist and then later revealed herself to be Eurus Holmes, and at the end of the episode shoots John Watson with a handgun. In the last episode, "The Final Problem", it is revealed that Sherrinford is in fact a high-security complex on an island to house some of the most dangerous criminals in the world, including Eurus. With Eurus having simply shot John with a tranquiliser dart, Sherlock and John stage a scenario where Mycroft will admit Eurus's existence. Mycroft explains that Eurus was the youngest child, 8 years younger than Mycroft