In SBS Monday/Tuesday drama "Secret Door" (script Yoon Sun Joo, director Kim Hyung Shik) the people who had betrayed Lee Je Hoon started to come to light and was drawing curiosity from the audience.
On October 14th, a staff member of "Secret Door" said, "There is definitely a person close to Lee Sun (played by Lee Je Hoon) who is threatening him. We're going to use the fact that this is a period drama and surprise Lee Sun in the most unexpected and detailed way so please look forward to this."
On the episode broadcast on October 13th, the crown prince Lee Sun found that the person who had been pinpointed was Kang Pil Jae (played by Kim Tae Hoon). However, the closer he got to the truth of the murder incident, he also started to get suspicious of the people around Lee Sun.
Near Lee Sun was his father Yeong Jo (played by Han Suk Kyu), his wife Lady Hyekyung (played by Park Eun Bin) and his teacher (played by Lee Won Jong).
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.