In Lonely World, which episode is the well invested by Aunt Feng?

Lonely aunt Feng threw herself into the well.

The Lonely World is directed by Shu-Pui Hou and Chi Wai Laam, written by Andy, starring Hu Bingqing, Andy, Jeremy Jones, Yixiao Li, Hansen, Huang Wenhao, Zou Tingwei, Lu Xingyu, Li Ruichao, Zhao Yixin, Gao Siwen and Liu Shuai, especially An Yixuan.

Based on the turmoil in the ruling and opposition parties in the late Northern Zhou Dynasty in ancient China, the play tells the story that the three daughters of Du, Prajna, Galo and Mantuoyin, as important ministers, gradually changed from noble families to royal daughters.