Weeks had passed since Mary's funeral, but John remained unable to accept reality, often seeing visions of Mary as if she had never left. To cope, he sought help from a psychotherapist. During one session, the roar of an engine and the shriek of police sirens erupted outside, stopping abruptly at the door. Opening it, John was astonished to see Mrs. Hudson stepping out of a supercar's driver's seat. She handed her phone to the pursuing police officer, who, upon hearing Mycroft's orders on the line, promptly withdrew. John had never known his elderly landlady possessed such skills; clearly, there was more to the widow of a drug lord than he understood. But there was more: Sherlock, handcuffed, was curled up in the car's boot.
John wasn't the only one suffering; Sherlock was also tormented by guilt, leading him to relapse into drug use. One late night, a woman named Faith Smith, using a cane, arrived at 221B. She claimed to be the daughter of the renowned entrepreneur and philanthropist, Culverton Smith. Years ago, she attended a meeting convened by her father, who intended to reveal a great secret but insisted on absolute secrecy. All attendees were required to take a memory-suppressing drug, causing them to forget the meeting within minutes. Stumbling back to her office afterward, Faith tried to write down the fading memory of her father's evil secret. It was too late; she remembered he intended to kill someone, but the name was lost. This word had haunted her for years, casting a shadow over her life.
Sherlock's mind, heightened by drugs, raced. He observed the visitor's appearance and self-harm tendencies. From the weight of her handbag, he deduced it contained a gun. Perhaps not wanting to see another woman die by gunfire, or maybe reminded of John by her cane, Sherlock spent the entire night with Faith. By dawn, they sat peacefully on a park bench. Sherlock agreed to take her case because one detail puzzled him: people have full names, so why did Faith remember the victim's identifier as a single word? Of course, his services required payment. Sherlock took the gun from her bag and threw it forcefully into the nearby Thames. But when he turned back, the bench was empty; Faith had vanished.
Sherlock's mind worked furiously to understand. He wandered the streets aimlessly, oblivious to honking cars. Suddenly, it hit him: Culverton Smith's target was "Anyone." Smith was a terrifying serial killer. When Sherlock next regained full awareness, he had been returned to Baker Street.
For the next three weeks, Sherlock obsessively gathered information on Culverton Smith. Finding no evidence of crimes drove him into a frenzy; he fired his gun at the walls and publicly accused Smith online. Mycroft, monitoring his brother's descent, tacitly approved Mrs. Hudson's plan to lock Sherlock in the boot and deliver him to John, leading to the strange scene at the therapist's office.
After much pleading from Mrs. Hudson, John agreed to see Sherlock. Before John could process the situation, his phone rang. The therapist, seeing John was occupied, answered it. It was Culverton Smith, sending a car to pick up Sherlock and John for a meeting—the time and place Sherlock had arranged two weeks prior. John opened the door to find a chauffeur and a waiting limousine, speechless. Only then did John think to ask Mrs. Hudson how she knew his location; Sherlock had told her.
Sherlock knew John too well. He knew John would see a therapist, that he cared for Rosamund on weekends, and that on weekdays, to avoid colleagues, he'd book lunchtime sessions near his clinic. A simple online search revealed the likely time and place. John hated being so transparent, but subsequent events proved Sherlock right.
Distrusting Sherlock's current state, John insisted on a medical evaluation before confronting Smith. The obvious choice was Molly. As if on cue, Molly rang the doorbell; Sherlock had summoned her two weeks ago, instructing her to bring an ambulance for the examination. John was utterly defeated.
John took the limo, while Sherlock traveled in the ambulance to Smith's corporate headquarters. Molly's prognosis was grim, but Sherlock was single-minded, focused on catching Britain's most prolific, undetected serial killer. The meeting with Smith was a media circus, full of feigned camaraderie. Sherlock used the opportunity to steal Smith's phone and send a message to "Faith."
Smith then invited them to tour a hospital he funded. Clearly playing a cat-and-mouse game, Smith mocked Sherlock's understanding of serial killers, implying he was powerless against a wealthy, powerful murderer. In his favorite room—the morgue—Smith was almost brazen. Like many serial killers, he harbored a desire to boast about his crimes. For three years, this urge had become uncontrollable, leading him to hold secret meetings and erase attendees' memories. The hospital was his perfect hunting ground; dead bodies here raised no suspicion. He spoke in metaphors and riddles, ensuring nothing was legally admissible.
Sherlock remained undeterred, knowing a confession wouldn't come easily. Only "Faith's" appearance could break Smith. The sound of a cane echoed, and "Faith" appeared at the morgue door. Sherlock's confidence vanished; this woman was not the one from the park. Amidst Smith's ridicule, even Sherlock doubted his drug-induced memory. Smith's taunts pushed Sherlock over the edge; he grabbed a scalpel and lunged. Enraged, fueled by grief and guilt over Mary, John punched Sherlock violently.
A bruised and battered Sherlock was placed in a secure private room, with Lestrade posting a guard. During a visit, John found Sherlock asleep. John brought his old cane, a symbol of how Sherlock had once helped him overcome his own psychological hurdles. He hoped it would inspire Sherlock now. After receiving a call from Mycroft, John left hurriedly. Alone and vulnerable, Sherlock lay in bed when a section of the wall slid open, revealing Culverton Smith.
Smith had built secret passages during the hospital's construction by frequently changing architects and workers. These passages allowed him to move unseen and kill patients unnoticed. Today was his triumph: killing the great Sherlock Holmes. He had meticulously checked Sherlock's clothes upon admission, finding and disposing of three suspected recording devices. Confident, he confessed his crimes in detail, preparing to kill Sherlock.
As Smith gloated, John arrived at Baker Street, where Mycroft was searching for clues about his brother's self-destructive behavior. Mycroft hinted at another sibling in the family with similar issues. John found the answer on a DVD left by Mary, asking Sherlock to "save John Watson." Mary understood John's nature: he would reject direct help but couldn't resist helping someone in need. Sherlock's entire dangerous charade was a ploy to engage John's protective instincts.
Realizing Sherlock was in genuine peril, John sped to the hospital in Mrs. Hudson's car. The guard outside couldn't open the door and was seeking help. John broke it down to find Smith suffocating Sherlock. Cornered, Smith tried to lie, but he had missed a crucial detail: weeks earlier, Sherlock had planted a listening device in John's cane, anticipating John would bring it as a memento. Smith was arrested.
Back at 221B, Sherlock was recovering, still vaguely recalling "Faith." John admitted the ordeal had shaken him; the revelation that Mary and Sherlock had conspired to manipulate him was deeply unsettling. He hoped they could move past it with comforting words. But then, the distinctive tone of Irene Adler's text message sounded on Sherlock's phone, igniting a new fuse.
The clever, beautiful dominatrix was alive, a secret Sherlock had kept for
years. John deduced it must be Sherlock's birthday, prompting the risky message.
Pushing Sherlock to acknowledge his emotions, John confessed his own secret:
shortly after Rosamund's birth, he had begun an emotional affair with a woman he
met on the bus, exchanging texts until Mary's death. Furthermore, John pointed
out, Mary was wrong about one thing: he wouldn't have helped Sherlock simply
because he was in danger. It was only after seeing the DVD's contents that he
intervened. Unburdened, John wept with regret.
Days later, a relieved John met his therapist again, feeling things were improving. But trouble was brewing. The therapist revealed knowledge of Sherlock's other sibling—a sister. Removing her glasses and colored contacts, she revealed herself as "Faith," and also the woman from the bus. Her name was Eurus, sister to Mycroft and Sherlock. She knew how to exploit men's weaknesses; a little makeup, a smile, a cane, and they failed to recognize her. Smith had given her Faith's note, and she had orchestrated a grander scheme. Now that John knew the secret, she couldn't let him leave the room alive.
