Lee San 66 (이산 李祘) - 古裝韓劇 2007

A plot to poison the Queen is uncovered during a royal banquet at Giryuhyeon. While the King unexpectedly attends instead of the Queen, a mysterious court lady attempts to tamper with the food. The investigation reveals that the Royal Guard Captain, Hong Guk-young, orchestrated the assassination attempt to silence the Queen, who knew of his treasonous ties. Despite their deep bond, the King is forced to sentence his trusted friend to death.