Episode 5 In the middle of the night, San (actor Lee Seo-jin) is almost assassinated by an assassin but when the assassin is caught, he commits suicide by swallowing a pill before they can find out who sent him. San tries to get to the bottom of the assassination attempt but the body of the assassin vanishes and the crime scene is cleaned up when King Young-jo (actor Lee Sun-jae) appears to see if his grandson is alive. The king is confounded that he cannot see any signs of an intruder ever entering San’s chambers.
On the next day, Princess Hwa-wan (actress Sung Hyun-ah) goes to see her father, King Young-jo, who is full of worries. She tries to soothe his feelings and brings up last night’s incident. Princess Hwa-wan meets Choi Seok-ju (actor Cho Gyeong-hwan) at the market and gives him instructions to carry out.
Tired of fending of numerous assassination attempts on his life, San passes by the royal kitchen and remembers the time when he first met Song-yeon as a young boy. He meets Nam Sa-cho (actor Maeng Sang-hoon) and asks him to find out the source of the pill that the assassin swallowed to commit suicide.