Kim So-hyun and Yoon So-hee went through a power struggle.
On the latest episode of the MBC drama "Ruler: Master of the Mask", Mae-chang (Lee Chae-young) offered Han Ga-eun (Kim So-hyun) poison and passed out after drinking it.
False king Lee Seon (L) worried about her and took care of her. Prince Lee Seon (Yoo Seung-ho) sneaked in to see Ga-eun and cried over her. The Prince knew that the Queen (Kim Seon-yeong) was behind this. Kim Hwa-goon (Yoon So-hee) also knew that the Queen did this to get chosen as queen and spoke to the Pyeonsu.