(비밀의 문)is a September 22 - December 9, 2014 TV series directed by Kim Hyeong-Sik(SBS Episodes 24) South Korea.
Drama series follows the conflict between King Yeongjo ( Han Suk-Kyu ) and Crown Prince Sado ( Lee Je-Hoon ). King Yeongjo pursues strong royal authority, while Crown Prince Sado insists on equality for all.
A re-imagining of the legendary tale of the troubled father-son relationship between King Yeongjo (Han Seok Kyu) and his only son Prince Sado (Lee Je Hoon). While his father insists on a strong and centralized government, Crown Prince Sado promotes social justice and equality throughout the kingdom. Throughout eight fateful years, the strain on their relationship ? both familial and political ? eventually evolves into a total breakdown, ending with one of the most tragic stories in Joseon history.