During John's next session, his therapist reveals she was the one who had pretended to be both Faith, having gained the letter from Smith, whom she knew through a "Mutual Friend", and the woman with whom John had been texting. Upon inspecting the note under a black light Sherlock finds the message "Miss me?". Later having pulled himself back together and resumed taking cases, Sherlock discovers the note "Faith" had left him, proving the woman was real. Sherlock comforts him as he weeps, and John's hallucinations of Mary finally disappear. He also confesses to Sherlock that he had cheated on her by texting with another woman. John reconciles with Sherlock, telling him that he no longer blames him for Mary's death. Believing that he would be able to get away without proof of his confession, Smith is surprised when Sherlock reveals a recording device hidden in John's walking stick which John had left behind earlier. After seeing Mary's video for himself, John rushes to the hospital and arrives in time to pull Smith off Sherlock. Acting on Mary's orders, Sherlock puts himself in harm's way so that John would be compelled to rescue him, thus mending their broken friendship and "saving" himself. Unknown to him, the events were part of Sherlock's elaborate plot to expose Smith and fulfill Mary's last wish for Sherlock to "save John" by "going to Hell". Sherlock asks Smith to kill him, and Smith complies after confessing to his murders. Sherlock is then visited by Smith, who enters the room through a secret door. Sherlock is admitted into Smith's hospital, where John pays him one last visit. John attacks Sherlock out of anger, and blames him for Mary's death. Frustrated and suffering from withdrawal, Sherlock attacks Smith with a scalpel, but is stopped by John. Upon seeing her, Sherlock realises that she was not the woman who had come to his flat.
Sherlock tries to goad Smith into a confession just as Faith arrives, having been texted by Sherlock from Smith's phone. John asks Smith how he moves through all of the rooms freely, to which Smith replies that he has keys to the hospital.
Smith takes Sherlock and John to his 'favourite room', the mortuary, whilst repeatedly referring to the American serial killer H. He subtly hints to Sherlock and John at being a serial killer while meeting with a group of children at the hospital. Sherlock and John arrive at a studio to meet with Smith, during which it's revealed Smith has used Sherlock's accusation as a publicity stunt to support his new brand of cereal, making him a "Cereal Killer" and claiming Sherlock was in on the joke, after which the latter takes them to visit a new hospital wing for which he had been a major donor. Much to John's shock and annoyance, the arrival of a car sent by Smith, and of Molly Hooper with an ambulance to his therapist's house at the exact time, were all prearranged by Sherlock two weeks prior, even before John had chosen his new therapist. Sherlock accuses Smith of being a serial killer and asks John to help bring him down. Hudson takes Sherlock to see John while he is at his therapist's house for a session. Sherlock becomes obsessed with Smith, but his drug-addled antics frighten Mrs. Smith is a serial killer with the wealth and power to hide his crimes completely. As Sherlock stumbles back to his flat, he realises that the 'one name' was "anyone". Sherlock is momentarily overwhelmed by the side effects of his drug use and, upon gathering himself, finds Faith gone. Sherlock and Faith walk all night, and the following morning he decides to take her case. Mycroft tracks Sherlock's movement across the city, and calls John out of concern, accidentally implying existence of another Holmes sibling. Before she leaves, Sherlock realises that Faith is suicidal, and offers to walk with her around London. Sherlock dismisses her case as being too weird and refers her to Scotland Yard. She comes to Sherlock, who has started abusing drugs again, with the sheet of paper saying that there was a name – one word – that shook her.
Despite that, Faith is able to remember fragments and writes them down on a sheet of paper. Before he does so, he forcibly injects them with a serum that inhibits memory causing them to forget his confession. Culverton Smith, a prominent entrepreneur and philanthropist, gathers close colleagues, including his daughter, Faith, to confess that he is going to kill somebody. John, who is seeing a new therapist, conceals the fact that he is having hallucinations of Mary.
Sherlock remains distant to Watson, who is still grieving over the death of his wife, Mary (" The Six Thatchers"). ( January 2017) ( Learn how and when to remove this template message)
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