London serves first as a refuge Sir Charles Baskerville never reaches, then as the urban stage for a concealed investigation and a contest of surveillance. Its significance lies in the contrast between the safety and distraction Mortimer hopes the city will offer and the danger that follows the Baskerville heir there.

A journey interrupted

Concerned that Sir Charles’s heart condition and persistent anxiety were damaging his health, Dr. Mortimer advised him to spend a few months in London. Mortimer expected the distractions of town to restore him, and Roger Baskerville, a mutual friend, shared that view. The journey was imminent when Sir Charles died; London remained a proposed escape rather than a place he could reach.

The circumstances of his death explain the urgency behind that plan. The Baskerville Hall butler Barrymore sent the groom Perkins on horseback to fetch Dr. Mortimer, who reached Baskerville Hall within an hour. Mortimer checked the inquest’s account, followed Sir Charles’s footsteps down Yew Alley, and examined the place at the moor-gate where he appeared to have paused. He found no other tracks near the body besides Barrymore’s on the soft gravel, but at some distance he saw fresh, clear prints Barrymore had missed: those of a gigantic hound. Sir Charles lay face down, arms outstretched, fingers dug into the ground, and features contorted by powerful emotion, though his body bore no physical injury. The ash from his cigar had fallen twice, leading Mortimer to judge that he had stood at the gate for five or ten minutes. The intended London respite thus gives way to a death whose unexplained terror becomes the case’s central problem.

A concealed London investigation

London is also where Sherlock Holmes initially keeps his work hidden from Dr. Watson. Watson believes Holmes is at Baker Street in London handling a blackmail case; Holmes later explains that he wanted Watson to think so. By staying away from Baskerville Hall, Holmes could move about without alerting their opponents, and he kept himself an unknown factor until a critical moment. He had come to investigate in person, while the danger to Watson and Sir Henry made his concealment, in Holmes’s judgment, a precaution rather than a slight. Cartwright, a young worker from the express office, helped with Holmes’s basic needs and served as another pair of eyes.

Holmes’s secrecy also marks the difference between having suspicions and being able to prove them. He later resists Watson’s impulse to arrest Roger Baskerville: at that point, they have no case, no direct connection between the hound and Sir Charles’s death, and no proof that the animal had followed him. They had heard the hound but had not seen it pursuing Sir Charles. The London inquiry helps put Holmes back into the investigation, but the city itself does not supply the proof needed to turn suspicion into a prosecutable charge.

The pursuer and the warning

Roger Baskerville also uses London as a place to monitor the investigation and threaten the heir before he reaches the moor. He brought Beryl Stapleton to the city and lodged with her at the Mexborough Private Hotel in Craven Street. Distrusting her after she refused to help trap Sir Charles, and fearing the loss of his influence over her, he kept her imprisoned in her room while he went out disguised with a beard. He followed Dr. Mortimer to Baker Street in London, then to the station and the Northumberland Hotel. His hope was that Sir Henry might be killed in London without ever reaching Devon.

Beryl Stapleton understood enough of the danger to want to warn Sir Henry, but her fear of her husband—rooted in his brutal treatment of her—made an openly sent message perilous. She cut out words to assemble a warning and addressed it in a disguised hand. The letter reached Sir Henry and gave him his first notice of danger. London is therefore both the place where Roger Baskerville tries to close the trap and the setting from which Beryl manages to send a warning through it.

A trail from town to the moor

Roger Baskerville’s preparations for the hound began in the city. He needed an article of Sir Henry’s clothing so the animal could be set on his scent. The first boot obtained for him was new and useless for that purpose, so it was returned and replaced with an old one. Holmes treated the distinction as a decisive clue: the insistence on a worn boot made sense if a real hound was meant to track its wearer. A mundane hotel item thus carried the investigation from London’s rooms and corridors toward the threat waiting beyond the city.

Roger Baskerville shadowed the investigators in a cab and escaped their pursuit. He even sent Holmes’s own name back to him through the cabman, making clear that he had recognized Holmes’s involvement in London. Once he understood that the city offered no further chance to act against the heir, he returned to Dartmoor and awaited Sir Henry’s arrival. London’s role in the case is consequently brief but consequential: it is a planned refuge, a covert base, and a hunting ground where warning, surveillance, and preparation determine what happens next.