Which episode is Gu Jian's death in the East Palace?

According to Youku's query, in the TV series "East Palace", Gu Jian died in the 48th episode. The plot of the forty-eighth episode of "East Palace" focuses on the relationship between Li Chengyin and Gu Jian. In this episode, Li Chengyin finds Chai Mu and reveals his decision to let Gu Jian die. Chai Mu was very surprised, because he and Li Chengyin were both children of Gu Jian, and they were like brothers, so he couldn't understand Li Chengyin's decision to kill Gu Jian. However, Chai Mu tried to persuade Li Chengyin to let Gu Jian go, but he was finally carried away by hatred and failed. At the climax of the plot, Gu Jian was killed by an arrow, which was personally ordered by Li Chengyin. Chai Mu was filled with shock and fear when he learned the news. He tried to explain to Li Chengyin that Gu Jian was like brothers to them and should not be treated like this, but Li Chengyin was completely filled with hatred and turned a deaf ear to Chai Mu's words. "East Palace" was jointly produced by Tang De Film and Television, Youku, Lu Baihua Na, China Television Entertainment and MINO Film and Television, directed by Mu Geli and starring Chen Xingxu, Peng Xiaoran and Shawn Wei.