Tae Soo goes home while working on a case to celebrate his daughter's birthday; he is called to a police substation to pick up his daughter; Tae Soo realises that Ha Bin could be involved in a murder case and starts doubting her.

Tae Soo wants to trust his daughter however every piece of evidence he comes across reveals traces of Ha Bin; during his investigation, Dae Hong discovers that Tae Soo is involved in this case.

Jeong Hwan and Yong Soo visit Ha Bin at her place to interrogate her; Tae Soo goes around trying to check Ha Bin's alibi; Ha Bin suggests to Tae Soo that they move, but Tae Soo insists on staying until he catches the real culprit.

After Tae-su submits a keychain as evidence, the police discover a link to another case; Yeong-min is brought in for questioning once more.

Tae Soo gets a call from his wife; Joon Tae becomes increasingly apprehensive as the investigation progresses. Ha Bin, who believes her mother is a murderer, begins to dig deeper into her mother's past as an unidentified man follows her from behind.

A man who claims to be Song Min Ah's dad appears before Ha Bin; Ha Bin learns from the man that Tae Soo helped Young Min escape from the police; the police raid Young Min's place and take all the kids for questioning.