After marrying, Dr. John Watson parts ways with Sherlock Holmes and their shared residence on Baker Street, returning to his medical practice. During his rounds, he finds himself near Baker Street, and on a whim, decides to visit his old friend. Holmes, ever the detective, mentions that a prospective client of interest will arrive later that evening, ensuring Watson's curiosity is piqued.

An Unexpected Visitor

That night, a towering man, flamboyantly dressed and masked, arrives at Holmes's door. Despite the disguise, Holmes quickly discerns the visitor's true identity: King Wilhelm of Bohemia. The monarch reveals a delicate dilemma that brings him to Holmes.

Troubles of the Heart

Years earlier, the king had grown enamored with Irene Adler, a stunning yet tenacious soprano. Now, on the verge of announcing his engagement to a princess, the king faces a threat from Adler. She intends to release a compromising photograph that could jeopardize the royal wedding, as her demands for silence are unmet by the king. Despite multiple attempts to retrieve the photograph through undercover agents and break-ins, it remains hidden, forcing the king to seek Holmes's expertise.

Holmes's Ingenious Approach

The following morning, Holmes adopts the guise of a shabby horse groom and loiters near Adler's residence to gather intelligence. He learns of Adler's suitor, Godfrey Norton, and unwittingly becomes part of a curious incident. Both Adler and Norton head to a church separately, and Holmes, in his disguise, ends up witnessing their marriage. With Adler now wed, Holmes anticipates her imminent departure from London, prompting him to act quickly.

A Crafty Ruse

The next day, Holmes dons the attire of a clergyman and enlists Watson in his scheme. They visit Adler's home separately. Watson observes Adler's arrival and notes the commotion that ensues as a crowd surrounds her. Holmes, still in disguise, steps in to assist her, only to be seemingly attacked and injured, leading to his being carried inside Adler's home. Positioned on a couch within Watson's view, he signals for Watson to execute the next phase of the plan. Watson hurls a smoke bomb through a window, inciting cries of "Fire!" amidst the chaos, Holmes slips out to join Watson, explaining the ruse as they retreat to Baker Street.

The Plan Unfolds

Holmes's deduction was that in an emergency, Adler would instinctively go to the photograph's hiding spot. By orchestrating the disturbance, he observed where she ran, uncovering the secret location of the photograph. The next day, Holmes intends to revisit Adler's residence with the king to seize the photograph while Adler is absent. As Holmes and Watson near their destination, a cloaked figure passes, bidding Holmes a good evening.

A Twist in the Tale

The following morning, Holmes and the king arrive at Adler's home, only to be met by an elderly woman who relays that Adler and her husband have departed for their honeymoon, aware of Holmes's impending visit. Startled, they are ushered into the drawing room where Holmes discovers a photo of Adler and a letter addressed to him in the hidden compartment.

Irene Adler's Masterstroke

The letter reveals Adler's savvy awareness of the king's potential use of an agent. Suspecting Holmes after he entered her home in disguise, she cleverly donned her own disguise and shadowed Holmes and Watson to Baker Street. Having found love with Godfrey Norton, Adler reassures the king that the photograph will no longer be a threat to his marriage.

The Conclusion

King Wilhelm, both relieved and impressed, expresses his gratitude to Holmes, offering a valuable ring as a reward. Holmes declines the ring, instead requesting the photograph of Irene Adler. The king obliges, providing the photograph, leaving Holmes with a token of the woman who outwitted him.