Joseon X-Files () is a 2010 South Korean television series starring Kim Ji-hoon, Im Jung-eun, Kim Kap-soo and Jo Hee-bong. It aired on tvN from August 20 to October 29, 2010, on Fridays at 24:00 for 12 episodes.
The historical drama is based on cases detailed in the Annals of the Joseon Dynasty while incorporating mysterious and supernatural elements.
The original Korean title's literal translation is Secret Investigation Records, and the series is also known as Joseon X-Files: Secret Book ().
Mysterious incidents are recorded in the Annals of the Joseon Dynasty that cannot be explained through science.
In this Joseon-era alternate history, Kim Hyung-do (Kim Ji-hoon) is an inspector with a strong focus on investigating into administrative misdeeds. This brings him into direct contact with a secret organization within the government. Dealing with strange, paranormal and possibly alien phenomena, the duty of this organization is to keep everything under control, leaving only secret records. Occurring during the reign of King Gwanghae, the episodes make various allusions to the political turmoils of the period. These individual stories are:
In these various contexts, investigator Kim Hyung-do avoids superstition and searches for realistic explanations while investigator Heo Yoon-yi (Im Jung-eun) is more open to supernatural possibilities, including secrets of her own. The finale doesn't explain everything. Kim Hyung-do's last reply to Heo Yoon-yi is only "I know who you are".
83 other actors are named in the hard-subbed credits. Among them: