The Hound of the Baskervilles is the third of four crime novels by Sir Arthur Conan Doyle featuring the detective Sherlock Holmes.
Sir Charles Baskerville is found dead on the grounds of his country house, Baskerville Hall. The cause is ascribed to a heart attack. Fearing for the safety of Sir Charles's nephew and only known heir, Sir Henry Baskerville, coming from Toronto,Canada to claim his inheritance, Dr James Mortimer travels to London and asks Sherlock Holmes for help. Mortimer explains that the Baskerville family is afflicted by a curse. According to an old account, over two centuries ago Hugo Baskerville was infatuated with a farmer's daughter. He kidnapped her and imprisoned her in his bedroom. She escaped and the furious Baskerville offered his soul to the devil if he could recapture her. Aided by friends, he pursued the girl onto the desolate moor. Baskerville and his victim were found dead. She had died from fright, but a giant spectral hound stood guard over Baskerville's body. The hound tore out Baskerville's throat, then vanished into the night. Sir Charles Baskerville had become fearful of the legendary curse and its hellhound. Mortimer decided that Sir Charles had been waiting for someone when he died. His face was contorted in a ghastly expression, while his footprints suggested he was running from something. The elderly man's heart was not strong, and he had planned to go to London the next day. Mortimer says he had seen the footprints of a "gigantic hound" near Sir Charles's body, something not revealed at the inquest.
Intrigued by the case, Holmes meets with Sir Henry, newly arrived from America. Sir Henry is puzzled by an anonymous note delivered to his London hotel room, warning him to avoid the Devonshire moors. Holmes says that the note had been composed largely of letters cut from The Times, probably in a hotel, judging by other clues. The fact that the letters were cut with nail scissors suggested an authoress, as did a remnant whiff of perfume. Holmes keeps this last detail to himself. When Holmes and Watson later join Sir Henry at his hotel, they learn one of the baronet's new boots has gone missing. No good explanation can be found for the loss. Holmes asks if there were any other living relatives besides Sir Henry. Mortimer tells him that Charles had two brothers, Rodger and John. Sir Henry is the sole child of John, who settled in America and raised his son there. Another brother, Rodger, was known to be the black sheep of the family. A wastrel and inveterate gambler, he fled to South America to avoid creditors. He is believed to have died there alone. Despite the note's warning, Sir Henry insists on visiting Baskerville Hall. As Sir Henry leaves Holmes' Baker Street apartment, Holmes and Doctor Watson follow him. They realise that a man with a fake-looking black beard in a cab is also following him. Holmes and Watson pursue this man, but he escapes; however, Holmes memorises the cab number. Holmes stops in at a messenger office and employs a young boy, Cartwright, to go visit London's hotels and look through wastepaper in search of cut-up copies of The Times. By the time they return to the hotel, Sir Henry has had another, older boot stolen. When the first missing boot is discovered before the meeting is over, Holmes begins to realise they must be dealing with a real hound (hence the emphasis on the scent of the used boot). When conversation turns to the man in the cab, Mortimer says that Barrymore, the servant at Baskerville Hall, has a beard, and a telegram is sent to check on his whereabouts.
It is decided that, with Holmes being tied up in London with other cases, Watson will accompany Sir Henry to Baskerville Hall and report back by telegram in detail. Later that evening, telegrams from Cartwright (who was unable to find the newspaper) and Baskerville Hall (where Barrymore apparently is) bring an end to those leads. A visit from John Clayton, who was driving the cab with the black-bearded man, is of little help. He says that the man had identified himself as Holmes, much to the surprise and amusement of the actual Holmes. Mortimer, Watson, and Sir Henry set off for Baskerville Hall the following Saturday. The baronet is excited to see it and his connection with the land is clear, but finds the moor dampened. Soldiers are about the area, on the lookout for an escaped murderer named Selden. Barrymore and his wife wish to depart Baskerville Hall as soon as is convenient, and the Hall is, in general, a somber place. Watson has trouble sleeping that night, and hears a woman crying. The next morning Barrymore denies that it was his wife, who is one of only two women in the house. Watson sees Mrs. Barrymore later in the morning, however, and observes clear evidence that she has indeed been weeping. Watson checks with the postmaster in Coombe Tracey and learns that the telegram was not actually delivered into the hands of Barrymore, so it is no longer certain that he was at the Hall, and not in London. On his way back, Watson meets Jack Stapleton, a naturalist familiar with the moor even though he has only been in the area for two years. They hear a moan that the peasants attribute to the hound, but Stapleton attributes it to the cry of a bittern, or possibly the bog settling. He then runs off after a specimen of the butterfly Cyclopedes, which was still found on Dartmoor until the 1860s. Watson is not alone for long before Beryl Stapleton, Jack's sister, approaches him. Mistaking him for Sir Henry, she urgently warns him to leave the area, but drops the subject when her brother returns. The three walk to Merripit House (the Stapletons’ home), and during the discussion, Watson learns that Stapleton used to run a school in Yorkshire. Though he is offered lunch and a look at Stapleton’s collections, Watson departs for the Hall. Before he gets far along the path, Miss Stapleton overtakes him and retracts her warning. Watson notices that the brother and sister don't look very much alike. Sir Henry soon meets Miss Stapleton and becomes romantically interested, despite her brother’s intrusions. Watson meets another neighbour, Mr. Frankland, an elderly lawyer. Barrymore draws increasing suspicion, as Watson and Sir Henry see him late at night walk with a candle into an empty room, hold it up to the window, and then leave. Realising that the room has a view out on the moor, Watson and Sir Henry determine to figure out what is going on. Meanwhile, during the day, Sir Henry continues to pursue Beryl Stapleton until her brother runs up on them and yells angrily. He later explains to the disappointed baronet that it was not personal, he was just afraid of losing his only companion so quickly. To show there are no hard feelings, he invites Sir Henry to dine with him and his sister on Friday.
Sir Henry then becomes the person doing the surprising, when he and Watson walk in on Barrymore, catching him at night in the room with a candle. Barrymore refuses to answer their questions, since it is not his secret to tell, but Mrs. Barrymore’s. She tells them that the runaway convict Selden is her brother and the candle is a signal to him that food has been left for him. When the couple return to their room, Sir Henry and Watson go off to find the convict, despite the poor weather and frightening sound of the hound. They see Selden by another candle, but are unable to catch him. Watson notices the outlined figure of another man standing on top of a tor with the moon behind him, but he likewise gets away. Barrymore is upset when he finds out that they tried to capture Selden, but when an agreement is reached to allow Selden to flee the country, he is willing to repay the favour. He tells them of finding a mostly burnt letter asking Sir Charles to be at the gate at the time of his death. It was signed with the initials L.L. Mortimer tells Watson the next day those initials could stand for Laura Lyons, Frankland’s daughter. She lives in Coombe Tracey. When Watson goes to talk to her, she admits to writing the letter in hopes that Sir Charles would be willing to help finance her divorce, but says she never kept the appointment.
Frankland has just won two law cases and invites Watson in to help him celebrate. Barrymore had previously told Watson that another man lived out on the moor besides Selden, and Frankland unwittingly confirms this, when he shows Watson through his telescope the figure of a boy carrying food. Watson departs the house and goes in that direction. He finds the prehistoric stone dwelling where the unknown man has been staying, goes in, and sees a message reporting on his own activities. He waits, revolver at the ready, for the unknown man to return. The unknown man proves to be Holmes. He has kept his location a secret so that Watson would not be tempted to come out and so he would be able to appear on the scene of action at the critical moment. Watson’s reports have been of much help to him, and he then tells his friend some of the information he has uncovered – Stapleton is actually married to the woman passing as Miss Stapleton, and was also promising marriage to Laura Lyons to get her cooperation. As they bring their conversation to an end, they hear a ghastly scream. They run towards the sound and finding a body, mistake it for Sir Henry. They realise it is actually the escaped convict Selden, the brother of Mrs Barrymore, dressed in the baronet’s old clothes (which had been given to Barrymore by way of further apology for distrusting him). Then Stapleton appears, and while he makes excuses for his presence, Holmes announces that he will return to London the next day, his investigations having produced no result.
Holmes and Watson return to Baskerville Hall where, over dinner, the detective stares at Hugo Baskerville's portrait. Calling Watson over after dinner he covers the hair to show the face, revealing its striking likeness to Stapleton. This provides the motive in the crime – with Sir Henry gone, Stapleton could lay claim to the Baskerville fortune, being clearly a Baskerville himself. When they return to Mrs. Lyons’s apartment, Holmes' questioning forces her to admit Stapleton’s role in the letter that lured Sir Charles to his death. They go to the railway station to meet Det. Inspector Lestrade, whom Holmes has called in by telegram. Under the threat of advancing fog, Watson, Holmes, and Lestrade lie in wait outside Merripit House, where Sir Henry has been dining. When the baronet leaves and sets off across the moor, Stapleton lets the hound loose. Holmes and Watson manage to shoot it before it can hurt Sir Henry seriously, and discover that its hellish appearance was acquired by means of phosphorus. They find Mrs. Stapleton bound and gagged in an upstairs room of Merripit House. When she is freed, she tells them of Stapleton’s hideout; an island deep in the Great Grimpen Mire. They look for him next day, unsuccessfully, and he is presumed dead, having lost his footing and being sucked down into the foul and bottomless depths of the mire. Holmes and Watson are only able to find and recover Sir Henry's boot used by Stapleton to give the hound Sir Henry's scent and find the remains of Dr Mortimer's dog in the mire.
Some weeks later, Watson questions Holmes about the Baskerville case. Holmes reveals that although believed to have died unmarried, Sir Charles' younger brother Rodger Baskerville had married and had a son with the same name as his father. The son John Rodger Baskerville, after embezzling public money in Costa Rica, took the name Vandeleur and fled to England where he used the money to fund a Yorkshire school. Unfortunately for him, the tutor he had hired died of consumption, and after an epidemic of the disease killed three students the school itself failed. Now using the name Stapleton, Baskerville/Vandeleur fled with his wife to Dartmoor. He apparently supported himself by burglary, engaging in four large robberies and pistolling a page who surprised him. Having learned the story of the hound, he resolved to kill off the remaining Baskervilles so that he could come into the inheritance as the last of the line. He had no interest in the estate and simply wanted the inheritance money. He purchased the hound and hid it in the mire at the site of an abandoned tin mine. On the night of his death, Sir Charles had been waiting for Laura Lyons. The cigar ash at the scene ("the ash had twice dropped from his cigar") showed he had waited for some time. Instead he met the hound that had been trained by Stapleton and covered with phosphorus to give it an unearthly appearance. Sir Charles ran for his life, but then had the fatal heart attack which killed him. Since dogs do not eat or bite dead bodies, it left him there untouched. Stapleton followed Sir Henry in London, and also stole his new boot but later returned it, since it had not been worn and thus lacked Sir Henry's scent. Holmes speculated that the hotel bootblack had been bribed to steal an old boot of Henry's instead. The hound pursued Selden to his death in a fall because he was wearing Sir Henry's old clothes. On the night the hound attacked Sir Henry, Stapleton's wife had refused to have any further part in Stapleton's plot, but her abusive husband beat and tied her to a pole to prevent her from warning him. In Holmes' words: "..he (Stapleton) has for years been a desperate and dangerous man.." It was his consuming interest in entomology that allowed Holmes to identify him as the same man as Vandeleur, the former schoolmaster.
