The Metropolitan Police has been caught up in a spate of suicide cases recently.Each of the deceased had taken a lethal poisonous capsule, and the bizarre manner of death attracted widespread attention.Desperate, Officer Lestrade, faced with a series of unexplained deaths, has to turn to unofficial detective consultant Sherlock Holmes for help.

Sherlock Holmes, a detective known for his excellent reasoning skills, took over the case and began an in-depth investigation.From the clues in the case, he keenly realized that this series of events was not a simple suicide.Hidden behind the scenes is a cunning serial murderer.

Meanwhile, John Watson, a doctor looking for a roommate in his apartment, meets Sherlock Holmes.The two hit it off and decided to work together to uncover the truth of the case.They moved into an apartment at 221B Baker Street and became new partners.

After a series of reasoning and tracking, the identity of the murderer gradually emerged.He is a London taxi driver who looks ordinary but hides a cruel heart.Sherlock Holmes single-handedly enters an empty college with the murderer.There, the killer finally revealed his modus operandi.He uses two capsules, one harmless and one deadly, to force the victim to participate in a game of life and death.After the victim makes a choice, the killer will swallow another capsule at the same time.However, is winning five consecutive games really just a blessing from fate?

At the critical moment, John Watson, who was following him, raised his pistol and shot the taxi driver dead.Under the questioning of Sherlock Holmes, the murderer who was about to die finally revealed the mastermind behind the entire incident - Moriaty.

The story of this episode is adapted from Holmes and Watson's first case: “A Study in Scarlet”.The screenwriter made many clever and interesting adaptations based on the original work.For example, the death message “RACHE” left by the victim was interpreted by Holmes as the German “RACHE” in the original work.But in the BBC drama, Sherlock Holmes rejected this explanation. He pointed out that “RACHE” is actually a female name-Rachel, the victim's dead daughter, and also the password in her mobile phone.It was this death message that helped Sherlock Holmes activate the global satellite positioning system and start tracking the prisoner.

In addition to the adaptation of this key detail, there are many elaborate arrangements in the play that pay tribute to the original work.For example, in London, a city where smoking is banned, the big smoker Sherlock Holmes lost his classic pipe and could only rely on nicotine patches to keep his mind excited.These designs all show the screenwriter's respect and creativity for the original work.