there. Holmes coldly refuses to tell him. Roylott becomes further enraged. The following excerpt is intended to establish that the conflict is between Sherlock Holmes and Dr. Roylott.

“I will go when I have said my say. Don't you dare to meddle with my affairs. I know that Miss Stoner has been here. I traced her! I am a dangerous man to fall foul of! See here.” He stepped swiftly forward, seized the poker, and bent it into a curve with his huge brown hands.

“See that you keep yourself out of my grip,” he snarled, and hurling the twisted poker into the fireplace he strode out of the room.

Disregarding Roylott's warning, Holmes, accompanied by Watson, goes down to Stoke Moran that very afternoon. He examines Helen's bedroom and Dr. Roylott's bedroom next door. He sees enough to satisfy him that Roylott is trying to kill Helen to prevent her from getting married, in which case he would have to pay his stepdaughter a substantial annual sum from her mother's estate. Holmes and Watson spend the night in Helen's bedroom. When they hear the low whistle at three o'clock in the morning, Holmes strikes a light and sees the "speckled band," which is a deadly poisonous snake trained by Roylott to crawl through the ventilator and down onto the bed. This was obviously the way Roylott killed Helen's twin sister Julia two years ago when she occupied this room. Holmes drives the snake back up the bell-pull and through the ventilator. The angered snake bites Dr. Roylott, and Holmes and Watson find him dead.

Thus the conflict between Holmes and Roylott, man-versus-man, is resolved when Holmes kills Roylott with his own poisonous snake. At the very end of the story the author, Arthur Conan Doyle, uses the following comments by Holmes to show that the conflict in "The Adventure of the Speckled Band" was indeed between Holmes and Dr. Grimesby Roylott. Roylott wanted to kill Helen; Holmes wanted to protect her. Holmes tells Watson:

"Some of the blows of my cane came home and roused its snakish temper, so that it flew upon the first person it saw. In this way I am no doubt indirectly responsible for Dr. Grimesby Roylott's death, and I cannot say that it is likely to weigh very heavily upon my conscience.”

The author Sir Arthur Conan Doyle sets up the story in such a way that the conflict becomes one between Sherlock Holmes and Dr. Grimesby Roylott. When Roylott is killed by his own snake at the end of the story, that resolves the conflict. Holmes even tells Watson:

"Some of the blows of my cane came home and roused its snakish temper, so that it flew upon the first person it saw. In this way I am no doubt indirectly responsible for Dr. Grimesby Roylott's death, and I cannot say that it is likely to weigh very heavily upon my conscience.”

Helen Stoner comes to Sherlock Holmes early in the morning. She tells him a long tale about her family and about her sister Julia's mysterious death two years ago. She is fearing for her own life now because she has heard the same low whistle which Julia told her about shortly before she died an agonizing death. After Holmes promises to offer his advice and assistance, Helen leaves. Her violent, ill-tempered stepfather has been following her. He bursts into Holmes and Watson's sitting room unannounced and threatens Holmes with violence if he interferes in his affairs.

“I will go when I have said my say. Don't you dare to meddle with my affairs. I know that Miss Stoner has been here. I traced her! I am a dangerous man to fall foul of! See here.” He stepped swiftly forward, seized the poker, and bent it into a curve with his huge brown hands.

“See that you keep yourself out of my grip,” he snarled, and hurling the twisted poker into the fireplace he strode out of the room.

This is the only time Dr. Roylott appears in person and alive, but his presence haunts the rest of the story. When Holmes and Watson go down to Stoke Moran to examine the bedrooms, the reader always feels a danger that Roylott might return unexpectedly and become infuriated to find the detective inside his house after warning him not to meddle with his affairs. No doubt the country manor would contain several guns used for hunting, and Roylott seems quite capable of trying to commit murder.

After Conan Doyle introduces Dr. Roylott in person at 221B Baker Street, he has established that the conflict is between Holmes and Roylott. There is no other significant conflict in the story, and it is this battle of wits between the two cunning men that makes "The Adventure of the Speckled Band" so dramatic. The conflict is over Helen Stoner. Simply put, Dr. Roylott wants to kill her and Holmes wants to protect her. She is what is often called the MacGuffin in Hollywood parlance. She is the "bone of contention," what the conflict is about. There cannot be a serious and prolonged conflict in a story unless the conflict is about something specific. 

When Miss Helen Stoner comes to visit Sherlock Holmes, she tells him about her sister Julia's mysterious death two years ago. Her sister's dying words were “The speckled band!”

Miss Stoner cannot understand what these words mean. However, they are, she believes, the key to what happened to her sister, whom she strongly believes was murdered by their stepfather, Dr. Roylott. She fears Roylott is now trying to murder her. Holmes agrees with her and sets out to find speckled band that killed her sister. The story is called "The Adventure of the Speckled Band" because a speckled band is the murder weapon.

Because Roylott allows a band of Gypsies to live on the property at Stoke Moran, Holmes at first thinks the term "speckled band" refers to them. As he admits at the end, this supposition confused him at first, leading him in the wrong direction. Not until he and Watson hide in Miss Stoner's room and see the snake slither down the bell pull does Holmes put two and two together and realize that the "speckled band" that killed Miss Stoner's sister was a poisonous snake.

As he often does in his mysteries, Doyle has added a touch of the exotic and "Oriental" to his story: Gypsies (who were thought by the English to be of Egyptian descent and hence "Oriental"), a cheetah and baboon from India that wander the grounds, and Dr. Roylott's background as a doctor who worked in Calcutta and beat his Indian servant to death in a fit of rage. Whatever murdered the pure and wholly English Stoner sisters, it reflects the sense of an outside "pollutant" coming into England.

"The Adventure of the Speckled Band" is an example of a sub-genre of mystery stories commonly called a "Locked Room Murder Mystery." Julia was in her bedroom when she experienced the pains and psychological trauma that resulted in her death. Her door had been locked and the windows were covered with heavy iron shutters bolted on the inside. Julia and Helen both locked themselves inside their rooms at night because of their fear of the cheetah and baboon. In a Locked Room Murder Mystery the question is not so much whodunit? as how was it done?

There have been countless locked-room mystery novels and short stories published over the years. The prototype is undoubtedly "The Murders in the Rue Morgue" by Edgar Allan Poe. The following excerpt from a newspaper article quoted in that story describes the locked-room at the Rue Morgue where two women were horribly murdered.

“Four of the above-named witnesses, being recalled, deposed that the door of the chamber in which was found the body of Mademoiselle L. was locked on the inside when the party reached it....Upon forcing the door no person was seen. The windows, both of the back and front room, were down and firmly fastened from within....There was not an inch of any portion of the house which was not carefully searched. Sweeps were sent up and down the chimneys....A trap-door on the roof was nailed down very securely—did not appear to have been opened for years. 

In both stories the identification of the perpetrator becomes relatively easy after the detective figures out how it was possible to kill anyone who was securely locked inside a room. In the case of "The Adventure of the Speckled Band," Sherlock Holmes deduces that Dr. Roylott sent a poisonous snake through a ventilator, knowing that eventually it would bite Julia in her bed. In the case of "The Murders in the Rue Morgue," C. Auguste Dupin realizes that there must have been a way for the perpetrator to get inside the locked room, regardless of how thoroughly the police have searched the premises. It turns out that one of the windows was not firmly shut but only appeared to be so.

The theme of "The Adventure of the Speckled Band" can be called "a locked-room murder mystery."

Arthur Conan Doyle has Sherlock Holmes himself state the theme of the story at the moment Holmes and Watson enter Dr. Roylott's bedroom and find him dead.

"It is a swamp adder!" cried Holmes; "the deadliest snake in India. He has died within seconds of being bitten. Violence does, in truth, recoil upon the violent, and the schemer falls into the pit which he digs for another."

Holmes could not have known that by striking the snake and driving it back up the bell-rope and through the ventilator into Dr. Roylott's room he would be causing Roylott's death. This is understandable because, although Holmes seems to have some knowledge about that particular kind of snake, he did not know it be angry enough to bite its owner when it returned to his room. Neither did Dr. Roylott, apparently. He was not prepared from the snake's sudden return and did not have his noose ready to capture it.

Did Dr. Roylott expect Sherlock Holmes to arrive at Stoke Moran to interfere with his nefarious plans for his stepdaughter? Probably not. He may have thought that Holmes would not be sufficiently interested in Helen's distress to travel down there in person, since there was no fee to be gained. He may have thought that he had intimidated Holmes by twisting the iron polka and threatening him. And he felt somewhat protected by the cheetah and the baboon. At any rate, he didn't suspect that Sherlock Holmes was in the bedroom right next door to his own. It was poetic justice that he was killed by the snake he had used to kill Julia and was attempting to use to kill Helen.

Holmes' quotation is referring to Psalm 7:16 in the Old Testament. "His mischief shall return upon his own head, and his violent dealing shall come down upon his own pate."

In “The Adventures of the Speckled Band” the theme of the story is that evil will be punished by fate if not by man's instruments of justice.

The story demonstrates a kind of karma.  The doctor commits evil deeds, and those deeds pave the way for him to destroy himself.  He trains the snake to be his instrument of death, and the snake returns to him to kill him.

Holmes comments that a doctor who harms people is dangerous not just because he violates the Hippocratic Oath to do no harm.

When a doctor does go wrong he is the first of criminals. He has nerve and he has knowledge. (enotes pdf text p. 17)

The mystery centers on how Sir Grimesby Roylott, a dotor, manages to commit murder without anyone suspecting.  Holmes determines that he has used his reputation for eccentricity, and his animal collection, to accomplish this.  He trains a snake to do the murders for him.  Yet it is also the training of the snake that causes his demise, because Holmes attacks the sake and sends it back to him.

Some of the blows of my cane came home and roused its snakish temper, so that it flew upon the first person it saw. (p. 20)

Roylott would not have been killed if he had not trained the snake to do his dirty work.  He was punished by fate, karma, or his own evil.  In the end, he got what he deserved, and Holmes did not really have to play a part in it.

There is a simple theme in this story, good vs evil.  Dr. Grimbsy Roylott represents evil and Sherlock Holmes is a force for good.  If you wanted to characterize it more dramatically, you could say that it is a story about chivalry, where Sherlock Holmes is the white knight rescuing the damsel in distress, Helen Stoner from the evil clutches of the dark lord, Dr. Grimbsy Roylott.

Holmes emerges as a hero, slays the dragon (Roylott), rescues the girl and solves the mystery.

Another theme that emerges in this story is one of chaos, which is depicted by the decayed house and Dr. Roylott's behavior, particularly when he threatens Holmes with physical harm if he gets involved with Helen Stoner's case.  As contrasted with the world of Helen Stoner, who is engaged to be married and trying to live a traditional, normal life.

Roylott is trying to disrupt Helen's life, he wants to kill her so that he can hide his behavior and keep her money for himself.

Sherlock Holmes calls himself a "consulting detective." Nowadays we might call him a private detective, a private eye, or even a shamus. He is strictly a non-professional, and as such he is limited as to the kinds of cases he can take on. Then as now the police do not want private detectives interfering with murder cases. Holmes is able to get involved in solving murders only because he has done innumerable favors for Scotland Yard detectives and has allowed them to take all the credit for solving many cases he has solved himself. But it should be noted that Holmes rarely gets involved in murder cases before the police have been summoned to the scene of the crime. In the best-known Sherlock Holmes tale "The Hound of the Baskervilles," for example, Holmes is not trying to solve a murder but to prevent a murder. This is strictly legitimate work for a private eye, and many of the Sherlock Holmes stories are about clients who are in danger of being killed but are not actually dead.

In "The Adventure of the Speckled Band," Helen Stoner comes to Holmes for advice. She thinks she might be in mortal danger and is terrified. Holmes goes down to Stoke Moran accompanied by Watson, not to investigate the two-year-old death of Julia Stoner, but to protect Helen. It is noteworthy that he does not even try to arrest Dr. Roylott when he discovers what the vicious man has been up to; instead, the author conveniently arranges for Roylott to be killed by his own snake. Holmes simply does not have the authority to make an arrest. He does not even make the truth about Roylott's swamp adder or about Julia Stoner's death publicly known. Dr. Watson explains in the opening paragraph that the whole thing has been kept secret until he is currently revealing the truth in this story he entitles "The Adventure of the Speckled Band."

It is possible that I might have placed them upon record before, but a promise of secrecy was made at the time, from which I have only been freed during the last month by the untimely death of the lady to whom the pledge was given. It is perhaps as well that the facts should now come to light, for I have reasons to know that there are widespread rumours as to the death of Dr. Grimesby Roylott which tend to make the matter even more terrible than the truth.

This case is told to Holmes by a woman named Helen Stoner. Holmes and Watson, invite her to share her problem. Miss Stoner tells them that when their mother died Helen and Julia were left in the custody of their stepfather, a dangerous Dr. Grimesby Roylott.  They lived in fear and misery, despite of the being wealthy because of money left by their mother.  Julia mysteriously died two weeks before her marriage, and before she dies she said to Helen the words ‘speckled band’, but Helen doesn’t have a clue as to the meaning.  After two years Helen got engaged, her stepfather approved of it. A renovation of their house forced Helen to sleep in Julia’s room and she heard a whistle.  She lit a lamp found nothing, stayed awake and in the morning came to Sherlock Holmes for help. After she told him all her concerns they agreed to meet at her house but she should keep it secret from her stepfather. But she did not know Dr. Roylott followed her and threatened Holmes to back off, after she had left. Worried of Helen’s safety Holmes and Watson came to Stoke Moran and examined the room of Julia and Dr. Roylott. And Holmes noticed some odd things. Holmes asked Helen to signal to him and Watson to come back when Dr. Roylott sleeps. She does this and in the end Holmes and Watson solve the mystery.