Each of the family members remembers the day Mr. Yoo invited them over to his house; they remember the frightening incident that almost killed Yoo Bit-na, Mr. Yoo's daughter.

Everyone is shocked at Mr. Yoo's sudden death, especially Kim Ji-hye, who had given him sleeping pills the night before; she recalls the events leading to his death and the suspicious letter she found addressed to her.

Bit-na finds out that her father, Mr. Yoo, has fully recovered from his cancer; knowing this, she tries to figure out who might have known and questions the people around him.

Bit-na is hit by a golf club and is found to be unconscious the next day; she is lucky enough to be not seriously injured and decides to go back to the house to find out who the culprit was.

The quintet tries to prepare Ms. Park to act in front of the police; Sun and Bit-na find the same image of the map in Sul-young's laptop.

Hae-joon finds out that Jeong-wook was involved in his father's death; the police take Sul-young to the station to question her about the map to the safe that was found on her laptop.