Two years after the Reichenbach fall, John H. Watson's life seems to be gradually returning to peace.He works hard to leave the shadows of the past behind, and plans to enter a new stage of life with Mary Morstan, who combines beauty and wisdom.However, just when they were about to enjoy this harmony and romance, the resurrection of Sherlock Holmes broke the tranquility.

Watson is both happy and full of complicated emotions about Holmes' return.He knew very well that the appearance of this old friend meant that they would be involved in a series of complex cases and dangerous adventures.However, he could not deny that deep down he was full of expectations for Holmes' return.

This time, Sherlock and Watson's journey will be full of challenges.They need to uncover the conspiracy hidden under the streets of London, solve the sudden accident at the wedding, and at the same time face a notorious and insidious enemy-Charles Augustus Magnussen.Magnussen is known for his cunning and cruel methods, and his presence adds more complexity and uncertainty to the entire case.

In the process of solving these challenges, Sherlock and Watson's relationship also experienced tremendous changes.The tacit understanding and trust they once had had cracks due to Holmes' resurrection.Watson is confused and disturbed by Holmes' return, while Holmes attempts to reintegrate into their lives in his own way.