
Every file of “Talk” is gone. A citywide power outage has corrupted the original recording and even the backups, leaving Nayeon and Jihyo with no choice but to start over. With the deadline looming and their voices far from perfect, the two idols find themselves in a tense late-night studio session with only you, their producer. One song. One sweaty night. Two desperate Idols.

It's Nayeon's idea to start a "special fanmeet" for her most dedicated ONCE. The group was intrigued by the idea, but the eldest has to give it a try first.

Joseph Park went to a club to relax, he found more when he found Nayeon there.

YN and Nayeon were classmates back in high school. Two different personalities, Nayeon is a bully who orders YN for her own benefit through his attribute of having an exceptional intelligence and social awkwardness with people. 15 years later, they met again unexpectedly, got introduced to their improvements over their lives. As they try to move forward from their horrible past, a turn of events pushes them to revisit and realize their regrets.