Lee Je Hoon finally found the last remnants of evidence that his friend Suh Joon Young had left as a sign of the secret document.
On the 8th episode of SBS Monday/Tuesday drama "Secret Door" (script Yoon Sun Joo, director Kim Hyung Shik), Lee Sun (played by Lee Je Hoon) worked hard to try to put Yeong Jo (played by Han Suk Kyu) on the throne. As a result of this, he collaborated with the Noron faction and found a copy of the Maeng Yi secret document.
The actual culprit in the murder incident of Shin Heung Bok was Kang Pil Jae (played by Kim Tae Hoon). He was actually tortured by none other than the son Kim Moo (played by Kwak Hee Sung) who was sent by Kim Taek. Through this torture, he had not survived and perished. Thus, the only other person knowing the truth behind Shin Heung Bok's death had been eliminated and the finding of this secret document was important.
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.