I.O.I, a legendary girl group born from the 2016 audition program 'Produce 101,' made a miraculous reunion after 9 years. All nine members—Im Na-young, Kim Chung-ha, Kim Se-jeong, Jung Chae-yeon, Kim So-hye, You Yeon-jung, Choi You-jung, Kim Do-yeon, and Jeon So-mi—participated in a 10th anniversary project. Their title track 'Suddenly' reached number one on music charts on the day of their comeback. On June 13, 2026, MBC's variety show 'The Human Condition' episode 402 aired behind-the-scenes footage from their concert. Members displayed excitement and emotion throughout rehearsals and the performance, reuniting with fans who had waited nine years. Member Jung Chae-yeon shed tears backstage, reflecting on the possibility that this might be their final opportunity together. The concert featured beloved songs including 'Pick Me' and 'Shower,' performed by all nine members. The project, made possible through cooperation between the nine members and nine entertainment companies, demonstrated I.O.I's unchanged influence.