Sherlock Holmes is not the first Fictional Detective, but he’s widely perceived as the greatest: A man who solved crimes through the power of pure intellect, and who could deduce what a man ate for dinner last night by the color of his socks. When people think of Sherlock Holmes, they think of a classic case like “The Red-Headed League” in which Holmes unravels a seemingly pointless series of events to uncover a daring daylight robbery and catch the criminals in the act. In actuality, although Holmes has no abject failures to speak of, many of his cases fell somewhat short of complete success.

Many of them are as much character studies of life in Victorian London as they are mystery stories, and in quite a few no actual crime is committed at all. The stories in which Holmes earns less than an A+ grade fall into several distinct categories:

The case goes publicly unsolved ('The Boscombe Valley Mystery')

John and Charles are two friends from Australia, living as neighbors in England. When Charles is brutally murdered by Boscombe Pool, his son James is the obvious culprit. They’d been seen arguing near the pool earlier, and other circumstantial evidence points to James. Holmes runs through his usual set of observations and deductions to eliminate James and discover that John is the real culprit.

He and Charles weren’t the friends they seemed to be. In fact, Charles had been blackmailing James over their mutually seedy past in Australia, and when Charles demanded that his son marry John’s daughter Alice, John had had all he could take. Holmes confronts John, who will be dead of a terminal illness in a few months anyway.

He makes John sign a confession, but promises not to use it unless needed to keep James from being convicted of a crime he didn’t commit. In the end, James is acquitted at his trial, the confession goes unused, and as far as the world can tell, Holmes was unable to crack this one.

Holmes’ provisional theory is proved wrong ('The Adventure of the Yellow Face')

Holmes is hired by Grant Munro, whose wife Effie has been behaving strangely, asking for money for unexplained reasons, and conducting secret liaisons with someone in a nearby cottage. Holmes theorizes that Effie’s first husband, an American believed dead, is actually alive, and has returned to blackmail her. However, when Holmes investigates, he discovers that Effie is actually secretly meeting her own daughter, recently arrived from America. Effie’s first husband really is dead but had been a black lawyer, and Effie concealed it thinking her husband wouldn’t approve of her having a mixed-race child. When Munro learns the truth, he’s okay with it, and everything ends happily.

Holmes regards it as an embarrassing defeat and asks Watson to remind him of it whenever he gets too cocky. It doesn’t seem like much of a defeat to me. Holmes formed a theory, tested it, and disproved it on his own. But if Holmes considers it a defeat, it must be.

Passive roles for Holmes ('The Adventure of the Veiled Lodger')

There are several stories in which Holmes simply doesn’t play a very active role. In this one, a landlady tells Holmes of a very peculiar tenant, Mrs. Ronder, who rarely goes out and never shows her face. Holmes recognizes the name as an old case in which two people had been attacked by a circus lion, with one killed and one disfigured. Before Holmes can do much investigating, Mrs.

Ronder calls him in to confess the whole story. Years ago in the circus, her husband had abused her.

She and her lover concocted a plan to kill her husband and make it look as though the circus lion had done it. When the lion was released, it attacked and disfigured Mrs. Ronder, and her lover ran rather than try to save her. As arresting her seems pointless at this late date, nothing is done. In fact, Holmes does virtually nothing in the entire story. Doyle himself seems to have recognized this flaw and tried to argue at the end that Holmes had somehow inspired Mrs. Ronder not to commit suicide, but he wasn’t fooling anybody.

The plot resolves itself. (from 'The Adventure of the Stockbroker’s Clerk')

Holmes is approached by Hal Pycroft, a clerk who had been about to accept a job with a major London firm when he was offered a better job by a new company in Birmingham. Funny thing though, the Birmingham company wanted him to just walk out on his job with the London company without ever reporting or resigning. Holmes reasons that the Birmingham company is a front and that an impostor will take Pycroft’s place with the London company. He goes to Birmingham to investigate but when he gets there, Pycroft’s employer attempts suicide. Checking the newspaper, they discover that the impostor had been discovered in London and the game was therefore up.

It would have ended the same way even if Holmes hadn’t been involved.

Solving the case does no good ('A Case of Identity')

Mary Sutherland’s fiancee has disappeared without a trace on their wedding day. Upon investigating, Holmes discovers that the fiancee was actually Mary’s own guardian in disguise. The guardian didn’t want to suffer the financial loss that would occur if his ward married, and so concocted a plan to ensure she never did. By giving her a fiancee and then taking him away, she would remain single waiting for him to return. However, learning this does no good. The guardian has done nothing for the police to hold him on, and Miss Sutherland is the sort who would never believe the truth even if Holmes told it to her, so he doesn’t.

The culprit gets away ('A Scandal in Bohemia')

This one is famous as the one where Holmes is beaten… By a woman! It’s quite overrated in that respect. Actually, the battle between Holmes and Irene Adler is more of a draw, in which each outflanks the other and both go away happy. Holmes is hired by the King of Bohemia, who is being blackmailed by a former mistress out to prevent his upcoming wedding by releasing details of their own torrid affair.

Holmes tricks Miss Adler into unwittingly revealing where her evidence (a photo) is hidden, but in so doing, Miss Adler recognizes him as the famous Sherlock Holmes and leaves town with the picture. It’s all okay, however, as Irene Adler is now engaged herself, and has no further interest in stopping the King’s marriage.

She keeps the picture for defensive purposes, should the King ever come after her, but has no intention of using it.

Holmes lets the culprit off ('The Adventures of the Devil’s Foot')

In some stories, Holmes catches the culprit but lets them go due to sympathizing with their position in some way. In this story, Holmes is hired by Mortimer Tregennis. His two brothers have gone insane and his sister died, while all three were sitting around playing cards one evening. A few days later, Tregennis too is found dead under the same circumstances.

Holmes finds traces of a mysterious hallucinogenic drug in the fireplace that accounts for the deaths. Apparently, Tregennis killed the others, but who killed Tregennis?

Holmes traces it to Dr. Sterndale, a researcher visiting from Africa. Tregennis stole a sample of the drug to get rid of his three siblings, and Sterndale, who had been in love with the sister, retaliated by giving the same treatment to Tregennis. Holmes sympathizes with Sterndale’s position and allows him to go back to his research.

Holmes steps outside the law ('The Adventure of Charles Augustus Milverton')

Holmes is engaged by Lady Eva Blackwell, to negotiate with Milverton, a professional blackmailer who has evidence sufficient to produce a scandal that would break up Lady Eva’s marriage plans. Holmes tries to impress the fact that Eva hasn’t got anywhere near the money Milverton is asking for, but Milverton doesn’t particularly care, as he was looking for someone to make an example of anyway, to encourage his other clients to ante up.

Holmes decides that the only thing to do is burgle Milverton’s house and obtain the damning evidence the hard way. Once there, he sees Milverton gunned down in cold blood by one of his victims. Holmes tosses all of Milverton’s blackmail evidence into the fire and barely manages to escape being nabbed by the Police himself. Holmes came that close to rattling a tin cup on the bars himself.

Holmes’ client dies ('The Five Orange Pips')

Holmes is engaged by John Openshaw, a country squire. Openshaw has received a mysterious threatening note asking him to leave the papers on the sundial. Funny thing, Openshaw’s father turned up mysteriously dead years back after receiving a similar message. Openshaw’s father's papers had been burned, so Holmes sends Openshaw home to leave a message on the sundial to that effect.

Holmes deduces that Openshaw’s father had been involved with the KKK in America, and had made off with some important documents that they needed: A little too late to save his client, however. By consulting shipping schedules, Holmes even deduces which American ship is carrying the culprits, and arranges to have them arrested upon their arrival back in the US. However, the ship is lost at sea before this can be done. Holmes’ deductive powers are in full bloom in this story, but he ends up with very little to show for it.

Holmes wins a very expensive victory ('The Adventure of the Final Problem')

Holmes is on the trail of Professor Moriarty, a man we’ve never heard of before, but who is, in fact, the mastermind behind all organized crime in London. Holmes conducts a brilliant investigation (that we hear almost nothing about), that gathers enough evidence to shut down Moriarty’s entire organization and get Moriarty himself sentenced to life in front of the firing squad.

When the police begin rounding everyone up, Moriarty himself evades the net, and Holmes decides it might be a really good time to take an extended vacation on the continent. Although he moves around a lot, Moriarty finally catches up with Holmes at the Reichenbach Falls in Switzerland. Being British, they have a fairly polite encounter with each other before fighting to the death, and in the scuffle, Holmes and Moriarty both go over the edge to their deaths. Holmes has defeated the greatest criminal mastermind of the age but at the cost of his own life. Worse yet, it was over 10 years before Conan Doyle could be prevailed upon to retcon the end of this story to make Holmes survive it.