In 208, Cao Cao personally led an army of 800,000 to attack Eastern Wu. Zhou Yu of Eastern Wu led the battle. Confrontation on the north and south banks of the Sanjiangkou.
One day, Zhou Yu took a boat to beijiang to inspect Cao Jun's water village, and found that Cao Jun's water village camp was very strict, who brought the soldiers, and inquired that it was Cai Mao and Zhang Yun who were the overseers. Zhou Yu thought to himself, if he didn't get rid of these two people, it would be difficult to break Cao Bing. Thinking about it, he ordered the sail back to the camp.
The next day, Zhou Yu received a military report saying that Cao Cao's army had been visited by Jiang Gan, and he was secretly happy in his heart and had a plan in mind. Zhou Yu invited Jiang Gan to the army, where he threw a banquet and received him warmly. He knew Jiang Gan's intentions, and confessed that when he met with his old friends today, he would only talk about old feelings and not talk about the affairs of the army. Jiang Gan listened, was shocked, and thought to himself, I was originally on the orders of the lord Cao Cao, who came to persuade Zhou Yu to surrender, who expected that he would close the door to death, how is this good? At the table, the wine glasses intersected, and the conversation and laughter were full of fun, and they drank until late at night. Zhou Yu pretended to be drunk and said to Jiang Gan, it is rare to get together with old friends today, sleep with me tonight, while talking, dragging Jiang Gan to his tent, when he got to the tent, Zhou Yu fell on the bed and slept. But Jiang Gan couldn't sleep at all, and by the glimmer of light in the account, he got up and looked around, and suddenly found that there was a pile of documents on the bookcase. Jiang Gan thought that there must be military secrets, so he quietly read and peeked at it, and there was a letter inside, and this letter was also written by Cai and Zhang Yun, the military governors of the Cao Army. The two of them were spies who secretly communicated with Eastern Wu.
In fact, this letter was prepared by Zhou Yu earlier, and deliberately let him see that it was the method of borrowing a knife.
However, Jiang Gan did not know the plan, so he hid the letter in his pocket and returned it to Cao Cao to see. Then, looking back at Zhou Yu, he was still deeply asleep. Zhou Yu also arranged in advance to send false information outside the account when the fourth change was changed. His subordinates told Zhou Yu that Cai Zhang'er would say that he was "anxious not to get down" and deliberately told Jiang Gan. When it was five days later, the sky was just dark, Jiang Gan got up and walked out of the tent, and drove the boat to Cao Ying with a cigarette.
Back at Cao's camp, Jiang Gan told Cao Cao about his experience in Eastern Wu and showed cao the letter. Cao Cao was originally a very suspicious person, and after reading the letter, he was furious and immediately called Cai and Zhang to the tent and said sharply: I ordered the two to march into Eastern Wu today. Cai Zhang and the two did not know the bottom, so they said: At present, the water army has not yet been trained, and it is not appropriate to advance lightly. Cao Cao listened and was furious. He roared again: "By the time the water army is trained, my first rank has been dedicated to Zhou Yu." However, when Cai Zhang and the two of them heard this, they were confused for a moment. In the midst of the chaos, he did not know how to answer, and when he was hesitating, Cao Cao ordered the two to be pushed out of the tent and beheaded.
When Cao Cao came over for a moment, he knew that he had won Zhou Yu's plan to kill people with a knife, and he regretted it too much.
