Boy did those words echo loudly throughout the season finale of Elementary on Thursday night. The episode followed Sherlock as he went to the darkest places of his past habits to find his old In Sherlock, Eurus Holmes (Sian Brooke), who is one year younger than her brother Sherlock (Benedict Cumberbatch), was the antagonist of the episode "The Final Problem.". Locked up in the high-security prison Sherrinford since her childhood, Eurus was considered a dangerous "era-defining genius" who used her intellect to "reprogram Sherlock Season 4 has been a long time coming. In fact, it's been in development for so long that it has kind-of felt like something that was still in the distant future. That is, until now. Sherlock won't return to our screens until 2017, but the release of the season 4 trailer at San Diego Comic-Con has ensured that the show is being talked about far and wide. A lot of the talk is speculation, of course, as it always is surrounding Sherlock, and at Comic-Con, the Sherlock producers teased fans with three clues to the season which have set tongues wagging. BBC's Sherlock was an extremely popular TV show that aired from 2010 until 2017. It brought actors Benedict Cumberbatch and Martin Freeman firmly into the spotlight thanks to their brilliant portrayals of the two lead characters. What made this adaptation so unique, though, was how it brought Sherlock Holmes into the 21st century. RELATED: 5 Reasons Why We Need Another Sherlock Season (& 5 We LiN6i.

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