Nirvana in Fire Episode 23

To verify the deal between Xia Jiang and Xie Yu, Prince Yu arranges a meeting between Xie Yu and Mei Changsu. Meanwhile, Mei has Fei Liu send Xia Dong a letter, asking her and Prince Jing to meet at the prison where Xie Yu is held. While interrogating Xie Yu, Mei receives information about why Xie Yu killed a certain man, Lin Congxin: Lin Congxin made a counterfeit letter written apparently by general Nie Feng, and Xia Jiang used the letter as evidence that the Chiyan army is planning to rebel. Xie Yu ambushed the unwitting general, making it seem that it was General Lin Xie of the Chiyan army who killed him. The truth is overheard by Xia Dong and Prince Jing. Prince Jing later visits Mei; he states he wants to re-investigate the Chiyan case. (Source: Wikipedia)