Family: The Unbreakable Bond episode 6 begins with Yoo-Ra having a flashback of her younger self with several other kids at a snowy place. A man groups them into pairs and sends them out to shoot at each other. Back to the present, the mysterious man who was talking to Yoo-Ra via Wolfe’s private phone in the last episode asks her if she still remembers him. Meanwhile, Chief Oh is at Yoo-Ra’s door, and Min-Seo is beside Yoo-Ra. Shaken by the phone call, Yoo-Ra hangs up and takes Min-Seo to sleep.
Chief Oh is waiting for Yoo-Ra to open the door when she receives a call that NIS member 404 (Do-Hoon) cannot be reached, so she goes. Back at the house, Yoo-Ra looks like she’s preparing herself in case an intruder comes.
Do-Hoon is looking for Koo In-Bo at the bus station. Do-Hoon found him, and they fought for a while in the last episode. Do-Hoon then sees Koo In-Bo driving away in his car. He tries to stop him, but he cannot, so he notifies the NIS.
At the NIS headquarters, Chief Oh is stitching up Do-Hoon’s wound he sustained from fighting Koo In-Bo. Do-Hoon tells her to stop snooping around Yoo-Ra, and Chief Oh tells him to stop ransacking her office. She found out Do-Hoon gained access to her safe in the last episode. The issue of Wolfe’s case comes up, and Do-Hoon asks Chief Oh why he’s excluding him from the case and what the tattoos on Wolfe’s and Carly Young’s chests mean. Chief Oh tries giving a vague answer, and when Do-Hoon pressures her, she tells him that that is her job to deal with and he should focus on his.
Chief Oh asks Do-Hoon to brief her on his current investigation target. He does and mentions his name is Koo In-Bo. When Chief Oh hears that name, she looks disturbed, and Do-Hoon notices. Chief Oh then receives a text that Do-Hoon’s car, which Koo In-Bo drove off with earlier, has been found. Do-Hoon tells Chief Oh he’ll handle the situation, but Chief Oh refuses and tells him he’s now off Koo In-Bo’s case.
Yoo-Ra goes to pick Do-Hoon up from the NIS headquarters (she still thinks it’s a gardening company). She had called him after the mysterious man called her, but, Do-Hoon didn’t answer. Do-Hoon is surprised and happy to see her there.
Elsewhere, a man who sounds like a mysterious man that called Yoo-Ra, asks someone to book him the earliest flight to Korea. He then looks at a photo with the kids Yoo-Ra keeps having flashbacks of.
Yoo-Ra and Do-Hoon are heading home in a taxi when Yoo-Ra asks him if he would want them to move from where they live. But, Do-Hoon doesn’t hear her because he’s asleep.
The next day, Yoo-Ra wakes up and finds Do-Hoon and Min-Seo aren’t in the house, so she starts panicking. But, Do-Hoon and Min-Seo had just gone out for a morning run. Yoo-Ra gets mad at Do-Hoon and Min-Seo, which surprises them. Min-Seo later tells Do-Hoon that Yoo-Ra may be upset because of Woong-So’s upcoming 80th birthday party. Do-Hoon then goes to Yoo-Ra and tries to cheer her up. Yoo-Ra expresses her worry about persuading Woong-So to agree to the party, and Do-Hoon assures her he’ll handle it.
Butterfly is at a restaurant with her daughter, Kyung-Jin, and granddaughter, Won-Young. It seems they’re estranged because Kyung-Jin tells her that that would be the last time she’ll be seeing her and Won-Young, even though she no longer holds a grudge against Butterfly for leaving her when she was young. They leave, and Butterfly leaves later. When she goes to pay the bill for their meal, the cashier tells her it’s already been paid. It turns out Chief Oh is the one who paid the bill.
Do-Hoon is at Koo In-Bo’s, ransacking it; when he finds a safe, so he takes it. While in his car, Chief Oh calls and scolds him for being involved in Koo In-Bo’s case when she instructed him not to. Do-Hoon then remembers how Chief Oh looked disturbed when he asked her about Wolfe and Carly Young’s tattoos and mentioned Koo In-Bo’s name earlier. Do-Hoon wonders if Koo In-Bo was involved with Wolfe. As he exits the hotel, Koo In-Bo watches him from afar.
Yoo-Ra is at a real estate office when she sees a newlywed couple taking up a mortgage for their new house. She fondly remembers when she and Do-Hoon bought the house they now live in. Do-Hoon then calls to tell her he’s settling the issue about the birthday party with Woong-So.
Do-Hoon now knows why Woong-So doesn’t want to have the birthday party, so he asks him who he’ll choose between, Ms Yoon and Ms Park, to attend the party. Woong-So, who’s drunk, says he wants Shin-Ae because she’s the only one he loves. This pisses Do-Hoon off, and he continues pressing him to decide who he wants at his party between Ms Park and Ms Yoon, but, Woong-So passes out. Do-Hoon then decides to take Ms Park and Ms Yoon’s contact so he can decide who between them will attend the party on Woong-So’s behalf.
The next day, Do-Hoon and Ji-Hoon go to meet Ms Park and Ms Yoon, and Yoo-Ra has a bad feeling about all this. They meet Ms Park, and before they tell her anything, they both get phone calls and walk away, leaving Ms Park alone in a restaurant. Later, Yoo-Ra and Mi-Rim scold Ji-Hoon for leaving Ms Park like that. Meanwhile, Do-Hoon is returning home when he calls Ma Young-Ji for updates on Koo In-Bo’s whereabouts. She was the one who called Do-Hoon when he was with Ji-Hoon meeting Ms Park earlier.
Yoo-Ra then calls Do-Hoon and scolds him also for leaving Ms Park hanging. Do-Hoon tells her he left Ji-Hoon with her, but, Yoo-Ra tells him Ji-Hoon also left. Do-Hoon begins yelling at Ji-Hoon, who’s with Yoo-Ra. He then tells Yoo-Ra that he’s at their building’s parking lot, parking his car. Yoo-Ra then tells Do-Hoon that she and Ji-Hoon are coming to meet him at the parking lot.
As Do-Hoon exits his car, Koo In-Bo comes and points a gun at him. Koo In-Bo leads Do-Hoon into his car and asks him where he kept his safe. They begin fighting, and Do-Hoon knocks Koo In-Bo unconscious with his gun. He then drives off and ignores Yoo-Ra, Ji-Hoon, and Mi-Rim, who are waiting for him in the parking lot.
Do-Hoon calls Jae-Yeol to ask him if he can keep Koo In-Bo hostage in his house, and he reluctantly agrees. Do-Hoon then places Koo In-Bo in something that automatically strangles him when he attaches it to his neck. Do-Hoon begins torturing Koo In-Bo for him to say the password to his safe. He says the password, and Do-Hoon finds a detailed list of the people Koo In-Bo has killed and the clients who ordered Koo In-Bo to kill these people.
Do-Hoon goes through the client list and sees Chief Oh’s name. He forces Koo In-Bo to confess who Chief Oh paid him to kill, and he tells him it’s a woman named Ma Yeon-Rim.
At the NIS headquarters, Chief Oh is at her office looking at photos she probably took of Kyung-Jin and her daughter while they were in the restaurant with Butterfly. She also has live security camera footage of Butterfly in her house. Butterfly calls Chief Oh and confronts her about spying on her daughter and granddaughter, and they begin going back and forth about Butterfly’s possible involvement with Warrior.
At Do-Hoon’s house, Min-Seo is studying with Bo-Seok while Ji-Hoon seems like he’s dressing to go out. Min-Seo goes to Yoo-Ra’s café to inform Yoo-Ra that Ji-Hoon has left. Later while tidying up the café, Yoo-Ra takes out a purse with bullets, and one is missing (it may have been the one she used to kill Wolfe). Yoo-Ra starts having a flashback of the boy with the bloody face again. It turns out the boy is the mysterious man who called her via Wolfe’s private phone.
That man is on his way to Korea. He arrives and gets in trouble because he unknowingly cuts the line of people waiting for a cab at the airport. Fortunately, a woman helps him and offers to share a cab with him. While in the cab, the woman goes on and on about her ex-husband, which makes this man uncomfortable. It turns out this woman is Chae-Ri, Jae-Yeol’s ex-wife.
Chae-Ri visits Jae-Yeol, who’s happy to see her, but she asks Jae-Yeol to kill a man for her. At the NIS headquarters, Chief Oh texts someone to get rid of Koo In-Bo and keep an eye on Do-Hoon (404). Do-Hoon comes to her office and asks her about Koo In-Bo’s case and his whereabouts (he’s pretending he doesn’t know). Do-Hoon then asks Chief Oh if NIS now asks an outsider to do their job (he’s referring to Chief Oh asking Koo In-Bo to kill Ma Yeon-Rim). Do-Hoon then assures Chief Oh he’ll always be there if she needs him.
Ms Park visits Woong-So and tells him Ji-Hoon expressed how much he misses Shin-Ae, so she has decided not to attend his birthday party. Meanwhile, Ji-Hoon looks like he’s about to jump off a bridge when he receives texts from the rest of the family applauding him for solving Woong-So’s issue with Ms Park and Ms Yoon. He also gets a text from someone who was threatening him earlier, threatening him again. Do-Hoon returns to Jae-Yeol’s house, where he has held Koo In-Bo, hostage, and finds he’s been murdered.
It’s Woong-So’s birthday party the next day. And the family can’t seem to find out where Ji-Hoon is. At the party so, they go looking for him. They find him at Shin-Ae’s grave, and as expected, they’re mad.
Ji-Hoon confesses he bought the space behind Shin-Ae’s grave for Woong-So as he wished to be buried beside Shin-Ae, but he was scammed. This explains the threatening messages and calls he’s been getting. They go back to the party’s venue and find everyone has left – but they still party by themselves anyway.
The family heads back home, and Yoo-Ra goes ahead with Min-Seo to the house and finds the mysterious man at their door!
This episode has revealed Yoo-Ra has a much darker past than we thought. There’s a possibility she was a member of the MDG Union, so maybe the mysterious man who entered the picture was together with her in the union.
As for Chief Oh, her connection with Butterfly and Koo In-Bo, and her taking Do-Hoon out Wolfe and Koo In-Bo raises more suspicions about her involvement with the MGD Union. As for Ji-Hoon, I honestly can’t stand how selfish and inconsiderate he has been in this and previous episodes.