On September 7, 2015, JYP Entertainment’s first K-Rock idol group DAY6 debuted with their mini-album The Day and music video for title track “Congratulations.” For their debut, DAY6 didn’t hold anything back, playing a role in the composition of the lyrics and music for all six pop-rock tracks. 

The Music Video

If you’ve seen Train to Busan or Parasite, then the protagonist of the music video should seem familiar—after all, he is Choi Wooshik, who played Yongguk the baseball player in the zombie thriller and Kevin the tutor in Parasite. The music video starts with Wooshik sitting in an empty train car, staring down at his phone. Eventually, the train stops and a couple boards the train, only for the girl to be Wooshik’s ex-girlfriend. Between moments of awkwardness where Wooshik and the girl make eye contact, we’re treated to happier moments in time from when the two were happy together as well as scenes of DAY6 performing. The video plays off the lyrics very well, the two creating a story of heartbreak that eventually transitions to acceptance as Wooshik stands up on the train and leaves, this time being the one to put the other in the past.

The Debut Performance

Rather than have a debut stage for “Congratulations,” DAY6 had a mini showcase the day before the mini-album was released, where they performed “Congratulations,” “Free하게 (Freely),” and “버릇이 됐어 (Habits).” The six members wore skinny jeans and t-shirts, with some members wearing blazers or vests as well. The only member who didn’t stick with this formula was Wonpil, who wore a long sleeved screen tee. The stage was relatively minimal in terms of decorations, with only stage lights and two small screens displaying video packages for each of the tracks being the only distractors from DAY6.

The Legacy

The Day was a successful debut for DAY6, with the album peaking at No. 6 on the Gaon Weekly Album Chart, No. 12 on the Gaon Monthly Album Chart, and No. 2 on the Billboard U.S. World Albums Chart. “Congratulations” also charted, with the track peaking at No. 58 on the Gaon Weekly Digital Songs Chart and No. 38 on the Gaon Weekly Download Chart.

Five years later, “Congratulations” is still one of DAY6’s most popular tracks, with the music video on the official JYP Entertainment YouTube channel ranking third in views, the first being their music video for “Shoot Me” and “You Were Beautiful (예뻤어)” having the second most views.

Unfortunately, this was the last release to feature the original six-member lineup, as keyboardist and vocalist Junhyeok left the group in February 2017, a month before the release of their second mini-album, due to personal reasons. In 2017, DAY6 released their first full-length album Sunrise with the re-recorded version of “Congratulations.” Their second full-length album, Moonrise, includes the re-recorded versions of the other five tracks from The Day, with those tracks and “Congratulations” including “(Final Version)” in the track titles and not including Junhyeok’s vocals.