Mr. Jabez Wilson consults Sherlock Holmes for the purpose of solving the mystery of his sudden loss of employment with the Red-Headed League.

Accordingly, Wilson is a pawnbroker at Saxe-Coburg Square in London. He has an assistant by the name of Vincent Spaulding, a man who seems to enjoy photography so much that he often sequesters himself in the cellar to develop his pictures. It is Vincent who brings an interesting advertisement to Wilson about a possible employment opportunity for red-headed men. When Vincent suggests that Wilson (who has flaming red hair) is well-suited for the position, Wilson agrees and decides to apply.

As the story goes, Wilson is hired by one Duncan Ross to copy out the Encyclopedia Britannica by hand at a pay of four pounds a week, for four hours a day. After eight weeks, Wilson is both surprised and frustrated to discover that his employment has been unceremoniously terminated without advance notification of any kind. As things stand, Wilson desperately needs Sherlock Holmes to help him find out what the Red-Headed League really stands for and why members of the League decided to play such a horrible trick on him. After all, he was starting to rely on the four pounds a week to supplement his meager income from the pawnshop.

The story concludes with Sherlock Holmes, Dr. Watson, Peter Jones (an inspector from Scotland Yard), and Mr. Merryweather (the bank director of the City and Suburban Bank) waiting in a bank vault for the notorious criminal, John Clay. Clay is none other than Vincent Spaulding, Jabez Wilson's assistant. His foray in the cellar was for the purposes of tunneling a path to the vaults of the City and Suburban bank, which abuts Wilson's pawnshop at the corner of the Square.

Jabez Wilson learns that he was hired by the Red-Headed League as a ruse to get him out of the pawnshop for a several hours a day so that Clay and his assistant could engage in their tunneling activities without benefit of observation.

Why does Jabez Wilson visit Sherlock Holmes?

Jabez Wilson not only needs money but is characterized as, among other things, a man who deals in money as a pawnbroker and who is very tight with his money. A detective as famous as Sherlock Holmes would charge a lot for his services, but Jabez comes to him because he has heard that Holmes will take cases on a pro bono basis if they interest him. As Wilson explains:

"I did not wish to lose such a place without a struggle, so, as I had heard that you were good enough to give advice to poor folk who were in need of it, I came right away to you.”

This may still not satisfy the discriminating reader, who will wonder why Wilson is going to such trouble when he should realize that the Red-Headed League, if it ever existed, is now defunct. So Holmes tells him he hasn't lost anything but is actually thirty pounds richer. This brings out a further explanation of Wilson's motives. He says:

"But I want to find out about them, and who they are, and what their object was in playing this prank—if it was a prank—upon me. It was a pretty expensive joke for them, for it cost them two and thirty pounds.”

It cost them two and thirty pounds, but Wilson may have only netted about thirty pounds after paying for the ink and paper. In addition to losing a profitable job which he was enjoying, Wilson is chagrined at the thought that somebody has apparently made a fool of him. A man with such blazing red hair must have been subject to many little jibes ever since his boyhood, and this could have led to Wilson's being overly sensitive.

It is mainly because of Wilson's parsimonious character that Holmes has the opportunity to get involved in a case involving the theft of 30,000 gold Napoleon coins from the underground strong-room of a bank. It would never occur to John Clay, who poses as Vincent Spaulding, that his employer would ever think of going to Sherlock Holmes for advice and assistance. And Wilson does not tell Clay about his visit to the detective because his suspicions of his assistant have been aroused by the questions Holmes has asked about him as well as the way Holmes has responded to the answers.

“What is he like, this Vincent Spaulding?”

“Small, stout-built, very quick in his ways, no hair on his face, though he's not short of thirty. Has a white splash of acid upon his forehead.”

Holmes sat up in his chair in considerable excitement. “I thought as much,” said he. “Have you ever observed that his ears are pierced for ear-rings?”

“Yes, sir. He told me that a gipsy had done it for him when he was a lad.”

Mr. Wilson, a pawnshop owner, worked at a part-time job, that his assistant convinced him to apply for, sponsored by the Red-headed League. His job was fairly easy, the only requirement was that he copy from an encyclopedia for four hours, 10 a.m. -2 p.m. , and NEVER, leave the room for any reason for he would be fired.  Despite the odd request, he did not mind the work, and welcomed the extra money he made.

However, one day, he showed up for work to find it empty, only a sign saying that the league was dissolved. Mr. Wilson attempted to find out what had happened on his own. When he had no luck with this, he sought out Sherlock Holmes to investigate the matter.

In "The Red-Headed League," why does Jabez Wilson visit Sherlock Holmes?

It is a little difficult to understand exactly why Jabez Wilson comes to Sherlock Holmes and what he hopes the great detective will do for him. Wilson has only the very faintest hope of regaining his post at the Red-Headed League with the extremely welcome four gold sovereigns every week. The author, Sir Arthur Conan Doyle, must realize that this is a rather sticky wicket to get through in plotting his story, so he has Holmes himself bring up the same question many readers would ask.

"On the contrary, you are, as I understand, richer by some £30, to say nothing of the minute knowledge which you have gained on every subject which comes under the letter A. You have lost nothing by them.”

“No, sir. But I want to find out about them, and who they are, and what their object was in playing this prank—if it was a prank—upon me. It was a pretty expensive joke for them, for it cost them two and thirty pounds.”

So Jabez Wilson mainly wants to find out why the man named Duncan Ross and whoever his associates are have played a prank on him and made him feel like a fool for spending eight weeks copying the detailed information in the Encyclopedia Britannica. He obviously doesn't like people laughing at him. His blazing red hair has made him hypersensitive because kids probably poked fun at him in school and he has been the butt of stupid jokes for most of his life just because of his red hair. When Holmes and Watson laugh at him earlier, he flares up:

“I cannot see that there is anything very funny,” cried our client, flushing up to the roots of his flaming head. “If you can do nothing better than laugh at me, I can go elsewhere.”

The fact is he cannot go elsewhere because he is trying to get an expert to help him for nothing. Sherlock Holmes is his only hope--and yet he risks alienating him by losing his temper. It is because he was fooled by pranksters who used his red hair for the purpose that Wilson is sufficiently outraged to want to track them down. Everybody has an Achilles heel, and Wilson's unusually brilliant red hair is his. Perhaps he did not intend to ask Sherlock Holmes to go out and investigate the case for him but only to give him some free advice. Holmes hasn't committed himself to doing anything except to listen to Wilson's story until the detective senses that there must be something much more important to the matter. Earlier he tells Watson:

As far as I have heard, it is impossible for me to say whether the present case is an instance of crime or not, but the course of event is certainly among the most singular that I have ever listened to.

It seems likely that Holmes would not have gotten involved in Wilson's case at all if the detective hadn't suspected that it was indeed "an instance of crime."

Wilson shows in various ways that he cares a great deal about money. He might be called a miser. He hires John Clay because Clay offers to work for half the customary wages. Wilson doesn't even subscribe to a newspaper, which helps to explain why he had never heard about the Red-Headed League before Clay told him about it. Of course, there was nothing to read about it in the newspapers because it had never existed. But at least Wilson would have been suspicious if he had been subscribing to a newspaper and had never seen a word about it before Clay showed him the ad. Wilson is captivated by the idea of being able to earn four pounds a week just for copying articles out of the Encyclopedia Britannica, and he is devastated when the job abruptly ends. (This is a possible weakness in the plot. Clay might have been smarter to keep Wilson employed at the League offices for a little while longer, rather than posting that notice that the League had been dissolved before he had gotten his hands on the French gold.) Wilson comes to Sherlock Holmes with his petty problem because he has heard that the great detective sometimes takes cases on a pro bono basis if they interest him. Wilson is actually hoping to get the services of the famous Sherlock Holmes for nothing. It is quite true that Holmes takes cases free of charge if they interest him, and Wilson is lucky that his case interests Holmes very much because he sees that there must be something of extreme seriousness behind this so-called Red-Headed League.

Wilson finds a sign on the door of the office where he'd been working for the league. It reads as follows:

"THE RED-HEADED LEAGUE
IS
DISSOLVED.
October 9, 1890."

He comes to see Holmes because his unexpected benefit (the league) is gone, because he doesn't know why, and because it is a mystery.