The Fatal Encounter (2014)

=> Both works are about King Jeongjo
=> Han Ji Min is in both but her character in Fatal Encounter is not as nice as her character in Yi San.

both tell the story of king Jeong Jo. TFE is action packed film focused on assassination attempts of King jj where Yi san is tell the life history of king jj including famous assassination attemps on his life.both are excellent and worth watching.
TFE has superb cinematography in a historical setting.

The protagonist this, King Jeongjo filme is a Prince Sado son's and it's a continuation of the filmd Sado, basically.

Both are historical films, which have interesting storylines. Jo Jung Suk acts in both films, although both characters he plays are vastly different from each other.

The premise of assassinating the King. One is about the era of Seong Jong and Jong Jong while the other follows the Noron plot to assassinate King Jeong Jo.