The thrilling premiere of "Watson" whisks us away to the majestic Reichenbach Falls in Switzerland, where our protagonist, Dr. John Watson, frantically dashes through the dense foliage. His destination: a dramatic confrontation between Sherlock Holmes and the nefarious Moriarty. Gunfire erupts, creating chaos, and the duo plummet into the roaring waters below. Watson, driven by a desperate need to save his friend, plunges in after him but is swept over the edge himself, sustaining a gash on his head and suffering a concussive blow.
Mercifully, Watson is rescued and transported to a hospital, where he is attended to by Shinwell Johnson. Johnson delivers the heart-wrenching news: Holmes has perished, and Moriarty's fate remains uncertain, presumed dead. However, an unexpected twist reveals that Holmes was actually wealthy, having bequeathed Watson a vision of a return to his medical roots and the establishment of a state-of-the-art clinic. Watson is further endowed with the liberty to choose his own medical team, with Johnson being handsomely compensated to serve as his trusted lieutenant and confidant. Thus begins Watson's journey into the Holmes Clinic.
Six months leap forward, finding Watson now at the helm of his burgeoning clinic, having fully recovered. His comrades include the academically inclined Dr. Sasha Lubbock, an adopted scholar who overcame humble beginnings in China to excel in medical school. Joining her is the tech-savvy Dr. Adam Croft and his identical twin, Stephens, united by their indistinguishable DNA and shared history. Adam, notably, harbors an unwavering fascination with eggs.
Rounding out the team is Dr. Ingrid Derian, renowned as the state's foremost neurologist, who collaborates closely with Watson and his esteemed colleagues. Meanwhile, Watson grapples with amnesia, his memories of the weeks preceding the Swiss tragedy remaining elusive. Nevertheless, fragments of Moriarty's image are slowly resurfacing, particularly the distinctive deformation of his two fingers, fused into the unmistakable shape of an 'M.'His latest patient is none other than Erika Filipello, a woman whose vision has become a blurred canvas, adorned with bizarre fragments dancing in her mind's eye, as though she is ensnared in a waking dream. Considering her familial ties to a grim history of fatal insomnia and her recent nights devoid of slumber, this state is not entirely detached from reality. Indeed, since her hospital admission, sleep has been a stranger to her. Watson visits Erika, who is erratic and deeply convinced that she suffers from FFI (Fatal Familial Insomnia). With a 23-week pregnancy weighing on her mind, her fear of her unborn child's fate is palpable, prompting her to implore Watson to preserve her life until her delivery.
The team dives into the challenge of diagnosing Erika, assembling all doctors to scrutinize her symptoms. It seems the FFI gene lurks in her family with a 50-50 chance of transmission. Through rigorous research into her father's medical history and deliberate detective work, Watson uncovers that Erika does not harbor FFI. Yet, the mystery of her condition persists.
During a conversation with Erika, Watson confides in her about a pivotal decision he made in London—choosing Sherlock over his partner, Dr. Mary Morstan. Ironically, Mary stands just outside the door, having stumbled upon their conversation and the ongoing investigation after a quiet reconnaissance of Watson's office. However, any potential reconciliation is dashed as Mary has moved forward, now cohabitating with her new partner.
Upon awakening the next morning, Erika discovers that her vision has abandoned her, shrouding her in a blanket of darkness. The sores circling her mouth hint at angular cheilitis, prompting Dr. Lubbock to conclude that a bone marrow transplant is her only hope. The only viable donor? Her brother, Damon Filipello, who has been out of sight for quite some time. Watson enlists the help of Inspector Gregson from Scotland Yard to locate Damon.
Damon is procured for the bone marrow transplant, but complications arise. Erika's cousin, Autumn, is also ill. The team admits her, treating her with caution as a potential infection, taking every precaution seriously within the intricate web of Sherlock's universe.
It doesn't take long for them to decipher that Autumn is afflicted with an enigmatic condition known as Songbird Fever. Erika, however, remains oblivious to this revelation. As Autumn's condition worsens and she develops resistance to antibiotics, Watson recognizes the urgency to delve deeper into this perplexing enigma.
Throughout this ordeal, Watson grapples with haunting flashes and strives to maintain composure amidst the chaos. He relies on a potpourri of medications to keep his symptoms at bay, and they serve their purpose, allowing him to eventually convene with his team to unravel the current case.
It transpires that we are dealing with two inherited disorders: Two-three syndactyly and orbital hypertelorism. These genetic traits have been passed down from Erika to her brother Damon and, eventually, to Autumn. The bombshell revelation, however, is that Erika and Autumn aren't merely cousins; they are also half-siblings.
This crucial insight paves the way for finding a solution and initiating treatment for both of them. Yet, Watson must confront his own past and forge a path forward with a renewed purpose.
As the episode draws to a close, we learn that Moriarty, miraculously, survived the fall and is still very much alive. He converses with Shinwell inside a cable car, where Shinwell hands over a briefcase filled with samples requested by the cunning doctor, before departing and leaving Moriarty to his devices.
