Tae Soo realizes that Ha Bin could be involved in a murder case and starts doubting her.

Tae Soo tries to believe Ha Bin, but he keeps finding evidence connecting her to the investigation.

Tae Soo's colleagues find out that his daughter is involved in the case. Tae Soo finds another crucial piece of evidence.

A keyring hints at a serial murder case, and police revisit Tae Soo as hidden secrets unfold.

Tae Soo discovers Ji Soo's chilling secret and tracks down Choi Young Min to learn more about what he knows.

Ha Bin meets a man who claims to be Song Min Ah's dad. Young Min tells Ha Bin who killed Lee Soo Hyun.