In "Mask" Joo Ji Hoon learned that Yoo In Young had killed Soo Ae.
On the SBS Wednesday/Thursday drama "Mask" broadcast on July 23rd, Ji Sook (played by Soo Ae) fought with Mi Yeon (played by Yoo In Young). Ji Sook was suspicious of her mother that had been suffering rom a sudden and unexpected death. Afterwards, she met her sibling Ji Hyuk (played by Hoya). Ji Hyuk revealed the fact that Mi Yeon came over on that day. Ji Sook would not let this go. Over and over, she asked Mi Yeon whether she had something to do with the death of her mother.
At this, Mi Yeon said that this was not something she was familiar with. The two people were having a conflict and Ji Sook was about to fall in the pool. Mi Yeon was surprised and held onto Ji Sook's hand. Min Woo (played by Joo Ji Hoon) was watching this from afar and thought back to the time that Mi Yeon had tried to kill Eun Ha.
Meanwhile, "Mask" is about a woman named Ji Sook who lives the life of a woman that has the same face. This is a thriller and romantic comedy mixed in one.
