Sherlock Season 4 Finale Trailer Released

Yesterday, Sherlock took fans for another turn when the second episode of Season 4 made its debut. The consulting detective found himself in a rather dangerous game alongside his friend Dr. John Watson and brother Mycroft. The thrilling episode left fans gaping, and next week will see the stunning storyline brought to an end when the Season 4 finale airs. "The Final Problem" is slated to hit PBS for U.S. audiences next Sunday, and now the trailer for the finale has been released.

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The short clip sees Sherlock and Watson in a tense situation as the trailer warns audience that their situation is "not a game" anymore.

"Every choice you've ever made, every path you've ever take - the man you are today is your memory of Eurus," Mycroft can be heard telling Sherlock who appears to be on the verge of tears.

Watson is then heard speaking, telling Shrelock, "Look, I know this is difficult, but you've got to keep it together."

Of course, the two men are referring to the shocker of yesterday's episode. In the last moments of "The Lying Detective," fans learned that Sherlock had a sister named Eurus who is just as clever as her brothers. The unassuming woman first appeared as the woman who involved herself in an affair with John before she disguised herself as a villain's daughter and even John's new therapist.

You can check out Sherlock's summary of the Season 4 finale below:

"In the final episode of this series, written by Mark Gatiss and Steven Moffat, long-buried secrets finally catch up with the Baker Street duo. Someone has been playing a very long game indeed and, alone and defenceless, Sherlock and Dr Watson face their greatest ever challenge. Is the game finally over?"

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Benedict Cumberbatch returns as Sherlock Holmes, with Martin Freeman as John Watson, Mark Gatiss as Mycroft, Rupert Graves as Inspector Lestrade, Una Stubbs as Mrs Hudson, Amanda Abbington as Mary Watson, Louise Brealey as Molly Hooper and Toby Jones as Culverton Smith.

Sherlock season 4 continues with "The Final Problem" on January 15th.