A South Korean spy named Shim Jung-Soo infiltrated North Korea's mines under the guise of a North Korean arrested for watching South Korean dramas. While working alongside Lee Soo-Jin, he tried to save her when she was knocked out by using his Charyeok beast. He instructed his Sapsal Dog to take her away from Ryu, who wanted to kill everyone and leave no witnesses. Shim Jung-Soo told the half-conscious Soo-Jin to live freely. In response, Ryu tried to kill him but instead blinded him with his Moonlight Sword technique.