The Shum/Vin Robinsons came to London and the first thing they had to do was rent a house. However, the rent in London is not cheap, and the rent price of the room provided by the agent is between 400 and 500 pounds per year. Just as they turned to leave, the agent mentioned a house with an annual rent of only 80 pounds, but the agent also doubted whether they could rent it, because the house had been registered for a long time, many people went to see it, but they were sent away by the landlord. The house is very good, and located in the bustling area of London, the price is incredible, so the Robinsons went to the door with the psychology of trying it out, and as a result, they successfully rented the house... This is the plot of the novel "The Adventure of Low-cost Rentals" by British writer Agatha Christie. When Detective Poirot heard what had happened to the Robinsons, he was keenly aware of the unusual price of the rent, so he began to carefully investigate the price of apartment rent in different parts of London, and eventually discovered the truth of the problem. Sherlock Holmes, the Great Detective, is also particularly price-sensitive. In the novel The Redhead, Holmes learns of a strange incident that happens to Jebez Wilson, a red-haired pawnshop businessman: Vincent, a pawnshop man, tells him about the Redheads, which, according to Vincent, was set up in accordance with the will of a red-haired millionaire in the United States, and used the interest on the estate to give the red-haired man a comfortable errand. As long as you are selected, you can comfortably do very little work, and get a stipend of 200 pounds a year... Another story takes place in The Copper Beech Case, in which a governess asks Holmes for help, and she is asked by her master to cut her hair short and wear the specified clothes to get a job that is much higher than the average social income. The governess's previous employer paid £4 a month, while the new employer generously started with an annual salary of £100, much to The Sherlock Holmes's suspicions. We always think that Conan Doyle and Agatha's detectives are good at reasoning logic, studying soot, familiar with poison, and in fact, they are also very sensitive to price, because the price is full of clues to discover the truth of the case. The price made it clear to the bizarre things: in The Adventures of Low-Cost Renting, Poirot followed the unusual clues of rent and finally discovered that the landlord's purpose was actually to find someone with the same name as a substitute for the dead; in "The Redhead Society", the reason why someone was willing to let the red-haired Wilson copy the book to get a high salary was nothing more than to support Wilson in order to dig a tunnel from his pawnshop to the bank vault; and in the story of "The Copper Beech Case", the employer was willing to pay teachers who were far above the market price The ulterior motive is to get the female teacher to pretend to be her imprisoned daughter, so that the daughter's lover can see it and leave with a dead heart, so that he will not marry the daughter to share the property. In our lives, unusual prices also often mean unexpected things. For example, someone bought a house at a price far below the market, and it turned out that the house was originally a murderous house; someone bought a very cheap car, and after inspection, it was found that the car had been overhauled; someone bought a very cheap brand-name electrical appliance on the Internet, and the result was a copycat... Commodities don't speak, criminals don't tell the truth, but prices do.