The next morning, Holmes handles the removal of Selden's body and tells Sir Henry to keep his dinner appointment with Stapleton, excusing himself and Watson. Holmes tells the baronet that he and his friend are going to London, and though Sir Henry is understandably alarmed, Holmes tells him to trust him. He also insists that the baronet deliver the same message to Stapleton and that he walk home alone across the moor after dinner.
Later that day, at the train station, Holmes sends Cartwright back to London with instructions to send a wire from London, in Holmes' name, to Sir Henry. Holmes hears from another man, Lestrade, whom he intends to enlist later that night.
Meanwhile, Holmes and Watson head over to Laura Lyons' place, and Holmes tells her of Stapleton's secret marriage. Shocked and visibly upset, Laura demands proof, and Holmes produces a photo of husband and wife. Laura spills the beans: Stapleton had offered to marry her if she got a divorce, an endeavor that would require Sir Charles' assistance. The naturalist wrote Laura's letter to Charles and then insisted she miss the appointment, suggesting that he himself would pay the expenses. Stapleton even convinced Laura to keep quiet, telling her that she might get in trouble.
After a long period of narration by Watson, the return of Holmes, like the unexpected appearance of the convict, can seem a bit jarring. Whereas Watson left things a bit looser, and more uncertain, after Holmes arrives, there is no more mystery left to solve. When he suddenly announces who the criminals are, we are left wondering how he solved the puzzle.
In this section, we learn that Stapleton is the culprit and that, in effect, all our speculations were useless since we did not have the key piece of information, Stapleton's identity and marital status. This allows the mystery to move much more quickly. Since Holmes knows what he is doing, how to get information out of people, and how to piece together the clues, the events follow one after the other and the denouement comes at an appropriate pace. If Watson's clue gathering allowed us a chance to participate, Holmes' tightlipped detection builds up the suspense even after the mystery's solved about what Holmes will do to catch the criminal. This section also recalls the themes of mistaken identity and entitlement. First, the convict is mistaken for Sir Henry because he is in his clothes, and as a result, the hound attacks him. Also, Holmes observes Stapleton's close resemblance to Hugo Baskerville. The villian's noble birth seems to make sense, because he feels like he is entitled to a large sum of money. Similarly, Beryl's rejection of Henry makes more sense, since she is not a lower-class woman rejecting a higher-class man, but rather, she is someone is already taken.
At the same time, this section reveals Holmes' own game of disguised identity. Holmes shows that he, a gentleman, lived like a convict. He looked for food and lived in a bare-bones dwelling. Even though Holmes also had clean collars and a willing helper-boy, the book still asks how Holmes could have managed in such dire conditions.