The comeback documentary of B.I.G (Gunmin, J-hoon, Heedo, and Jinseok) was released on its official YouTube channel on November 17th. The first episode drew attention as it showed the members expressing their honest feelings about the comeback.

In particular, J-Hoon said, "I expected that when I joined the army, B.I.G. would not be there when I returned. “When I was discharged from the military service, it was exactly when the members’ contracts ended," he confessed. Member Jin-seok also said, "I thought this FLASHBACK album would be the last one. So I thought I should try to do my best and limit more than I have ever done before," he said.

Gun-min met Black Swan's Young-Heun, who had been close since he was a trainee, and talked about his honest feelings. Gunmin surprised everyone by saying, "I really didn't want to make this B.I.G comeback." He shared his difficulties while working with NIK and B.I.G. activities. Gunmin said, "But now my mind has changed." There is only one reason. He explained that he changed his mind while recording the song, saying, "I felt like I was singing our song for the first time ever."