What kind of story does Sherlock's "Three Signatures" tell?

Detective Lestrade saw him and was about to catch the prisoner he had been catching for more than a year. However, at this time, Shylock suddenly sent a short message, which read for help. Lestrade gritted his teeth and gave up the honor of catching the prisoner. He returned to No.221b Baker Street, only to find that Shylock was uneasy about Watson's wedding, because Watson invited Shylock to be his best man, and the best man would give a speech at the wedding. Because Shylock is very unhappy about it.

Mrs Hudson brought Shylock morning tea and comforted him that marriage can completely change a person, which made Shylock even more sad. For Shylock Watson's wedding, Mary asked Watson to find some cases to distract Shylock. The wedding was held as scheduled, and the bridesmaids flirted with Shylock, but Shylock was unmoved. Mary was very happy when a man named David appeared at the wedding, but David was afraid to go near Mary. This is because Shylock investigated David long ago and warned him not to love Mary any more. If they meet, it must be in front of Watson.

Shylock threatened David, and David was very afraid. Watson was very surprised when his old boss, Colonel Schulto, appeared at the wedding. At the wedding, Shylock began to speak to the best man with sincere words and feelings. Shylock was invited by Watson to attend the wedding. Watson is one of the two favorite people in his life and is called Watson's best friend. This discovery shocked Shylock so much that he could hardly speak.

Everyone at the wedding was moved by Shylock's speech. Then Shylock began to tell interesting stories about Watson, mostly crime-solving dramas with Shylock. In most cases, Watson showed his courage, determination and loyalty. In The Mysterious Death of the Queen's Guard, Watson showed his professionalism as a military doctor and left a deep impression on Shylock. In the case of ghost dating, Shylock and Watson spent Watson's single night. They got drunk in the street and were finally rescued from prison by Lestrade. In the ghost dating case, a woman had a one-night stand with a man, and the man disappeared mysteriously.

Shylock didn't realize the relationship between the two cases at this time. But when making a toast at the wedding, Shylock realized the connection between two cases, that is, someone tried to assassinate Watson's boss at the wedding. Then Shylock used his intelligence to stop the case, and the wedding went smoothly. Watson and Mary danced to Shylock's beautiful violin, and Molly and her boyfriend embraced happily. After the wedding, the dance continued, and the banquet was bustling. Shylock put on his coat and walked alone in the night.