Duke Zhen did not believe that Prince Chu had been assassinated and killed. He worried this was a ruse by Prince Chu to lull him and the Crown Prince into a false sense of security.
He wrote a letter to his confidant on Mount Wuhua, inquiring whether there were any unusual happenings there. Although he believed Prince Chu would not find Mount Wuhua, he felt it was better to personally confirm just in case.
Duke Zhen was unaware that Mount Wuhua had long been under Prince Chu's control. His confidant had also been swayed by Prince Chu and had already betrayed him.
The confidant on Mount Wuhua replied to Duke Zhen, informing him that there were no anomalies at Mount Wuhua and everything was as usual. Yet, the copper supply at Mount Wuhua would not last much longer. At the end of the letter, he asked when Duke Zhen would send new copper, otherwise the work would have to be halted soon.
