In the southern United States along the Mississippi River, there is a town called Spat. This town is small and poor, and racial discrimination is very serious. A big entrepreneur in Chicago, Colbert, in order to help this small town get rid of poverty, came here to recruit workers and build a factory. Unexpectedly, he was murdered in a very In the Heat of the Night, and his 900 dollars disappeared.
For many years, Spat’s law and order situation has been relatively calm. This accidental murder made the Gales police officerwho had just been in office for two days at a loss . He assigned police officer Samto try to search for the suspect. When Sam came to the train station, he saw a black man who felt uncomfortable, and found that the black man was carrying a lot of cash, so he was arrested without questioning indiscriminately. Unexpectedly, this black youth named Tibbsplayed bylot of background. He is a capable criminal policeman in Philadelphia in the east. This time he is returning to visit his mother in his hometown.
Due to the complexity of the case, Gales had to ask Tibbs for help, although he looked down on black people in his heart. At this moment, police officer Sam caught another young man named Harveyand found the deceased's wallet and 300 yuan in cash on him. Sheriff Gales arbitrarily determined that Harvey was the murderer. However, Tibbs considered murder based on the wounds of the deceased. As the investigation progressed, the sheriff unexpectedly discovered that his subordinate Sam went to the bank to deposit $600 on the second day of the incident. Now, the sheriff put the murderer's hat on Sam's head again. Tibbs disagreed with this and explained to the Sheriff Gales that there was another murderer. Gales was stubborn and dissatisfied with Tibbs, and even ordered him to leave here immediately, not to intervene in the case. Because of the appearance of Tibbs, the racist black forces in this Spartan town are very angry, and they threatened that "this nigger will not live on Sunday." One day, Tibbs went to the streets to do business and was suddenly attacked by four white youths. Fortunately, Sheriff Gales arrived in time so that Tibbs was not assassinated.
Tibbs did not leave because of this, and still worked hard to collect clues to solve the case. At this moment, a young man named Purdy came to the police station to accuse Sam of raping his sister and pregnant her. Tibbs felt that this matter was strange, and decided to start from it and open the gap in the murder case
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