Kim Yoo Jung saw the murder of Suh Joon Young on site.
On the 2nd episode of SBS Monday/Tuesday drama "Secret Door" (script Yoon Sun Joo, director Kim Hyung Shik) broadcast on September 23rd, Suh Ji Dam (played by Kim Yoo Jung) saw the murder scene of Shin Heugn Bok (played by Suh Joon Young).
Shin Heung Bok had the weakness of Young Jo (played by Han Suk Kyu) and was going to cross the bridge when he felt a strange sense that someone was present.
Suh Ji Dam who was going to take care of the book business but sees someone falling from the bridge and head to the Soopo bridge.
Suh Ji Dam calls out the person who had fallen from under the bridge but there was no sign that anyone was present. Thus, he tries to check the person's neck.
Shin Heung Bok had already been killed and realizing this, he is suspicious that he was killed for his weaknesses.
Meanwhile, SBS Monday/Tuesday drama "Secret Door" is a period drama tha follows the conflict between King Yeongjo (played by Han Suk Kyu) and Crown Prince Sado (played by Lee Je Hoon). Kim Yeong Jo has an authoritarian ruling style whereas Crown Prince Sado insists on equality for all.