I.O.I, SeeYa and Secret turn 2026 into a girl group comeback wave

In 2026 K-pop, a series of long-awaited girl group returns is arriving almost all at once. I.O.I has already met fans again through a 10th-anniversary album and concerts, SeeYa has ended a long pause with a 20th-anniversary studio album and tour, and Secret is preparing new activities with a revised member lineup.

The key point is that these three teams cannot be grouped simply as acts calling up memories from the past. Each comeback is taking a different form, each fandom is reacting to a different part of the story, and each team still has separate questions to answer through new songs and future stages.

I.O.I reunites with a 10th-anniversary album and Seoul concerts

I.O.I began in 2016 as a project girl group, and its official activity period lasted less than a year. Even so, the group left an unusually long afterglow for fans. That is why its 2026 return has been received as more than a routine anniversary. The 10th-anniversary project did not stop at commemorative photos or a broadcast appearance. It continued with the May 19 release of a mini-album and the new song 'Suddenly,' followed by Seoul concerts from May 29 to 31.

The music video for 'Suddenly' does not simply pull the bright energy of 2016 back out of storage. Instead, it places the faces and atmosphere of members who have gathered again after time has passed at the front of the frame. Even the official video thumbnail shows the members leaning together beneath a large pink title. The choice presents the comeback not as a return that only borrows an old name, but as an attempt to show what the present-day I.O.I looks like when it stands together again.

The concerts made that effect more direct. The Seoul shows brought together early signature tracks such as 'Pick Me' and 'Dream Girls' with newer material including 'Suddenly' and 'SPF 100+.' The order of feeling mattered: the stage first opened the memories fans had been waiting to hear, then attached new songs to that familiar emotional base. When a returning group pushes only new music, the result can feel distant; when it repeats only older songs, the stage can look like a one-time event. I.O.I worked through that tension onstage.

SeeYa returns as a full lineup after 15 years and prepares an August national tour

If I.O.I's reunion is about reconnecting a time that was originally very short, SeeYa's comeback is about crossing a far longer absence. SeeYa debuted in 2006 and, after disbanding in 2011, has now resumed full-lineup activity for the first time in 15 years. Nam Gyu-ri, Kim Yeon-ji and Lee Bo-ram marked the group's 20th anniversary with a pre-release track, a fan-meeting and the May studio album 'First, Again.' The real point is that the group chose to link an album and performances rather than stop at a single commemorative event.

SeeYa's strength is still its voices. Because the group is remembered for songs including 'Scent of a Woman,' 'Salut D'Amour' and 'Song of Crazy Love,' the success of this comeback depends less on a flashy concept than on whether the music can still reach listeners naturally today. The three members' statement that this is 'not a nostalgia recall, but a new beginning' fits that question. Fans may expect the emotions they remember from the past, but the team also understands that it cannot last for long on those emotions alone.

The national tour 'The Fan,' which begins in Seoul on August 29 and continues to Busan, Daegu, Cheongju and Suwon, is the next test of SeeYa's return. The music release and album announce that the group is back; the tour will show whether the fans who waited are willing to move into actual concert venues. Whether the 20th-anniversary project ends as a welcome moment for longtime fans or becomes a case that draws middle-aged and older audiences into concert consumption will become clearer through the tour.

Secret previews 'Secret Flavor' with new member Yebin

The third axis, Secret, is harder to place on the same line as I.O.I and SeeYa. The team debuted in 2009 and, with 'Magic,' 'Madonna,' 'Shy Boy' and 'Starlight Moonlight,' represented the bright and broadly popular side of second-generation girl groups. However, team activity effectively stopped after 2014, and the member composition has also changed. The 2026 comeback is welcome news, but at this stage it is closer to rebuilding the team name with a new configuration than to a full-lineup reunion.

The currently known direction centers on Jun Hyo Seong and Jung Ha-na as activities are prepared with an added new member. The group has introduced new member Yebin and has also previewed the release of the special mini-album 'Secret Flavor.' For Secret, however, the core expectation from fans is balance rather than the name alone. The team needs to keep the bright melodies and approachable stage appeal of its past hits while making the changed member lineup fit without awkwardness.

Gaps of nine, 12 and 15 years have created different kinds of waiting

Even a simple comparison of the gaps shows how different the three assignments are. For I.O.I, returning after nine years, the central question is whether fans can see again the activity that ended too quickly. For SeeYa, returning as a full lineup after 15 years, the task is to prove that the group can still persuade listeners through song. For Secret, preparing team activity after roughly 12 years, the first step is to find the meeting point between a new member and the group's established color. These numbers are not just years on a timeline; they show the different ways fans have waited.

The continued visibility of second-generation girl group returns is also tied to changes in the age of the fan base. Fans who once followed these teams through broadcasts and music releases are now consumers who can buy tickets and goods themselves. That is why a reunion does not have to end as an online talking point. Market value appears when fans buy albums, go to concerts and bring friends back into the experience.

Still, there is no need to declare success too quickly. I.O.I still has to show whether the heat continues after Seoul through performances in Bangkok and Hong Kong. For SeeYa, national tour ticketing and live reactions will matter. For Secret, the first gate is how naturally the team color can be revived on the first stage after the new member is revealed. The 2026 comeback flow has started by confirming the power of old names, but the teams that remain in the end will be the ones that prove themselves again through new songs and real stages.