On August 3, 2015, Wonder Girls released their third studio album “Reboot”, their first comeback as a quartet after the departures of Sunye and Sohee, and with the return of original member Sunmi.

This album marked a pivotal moment in the group’s musical journey. Apart from the title track, the members took part in composing and writing the rest of the album, showcasing their evolution as singer-songwriters. The title track “I Feel You”—written by JYP Entertainment founder J. Y. Park—featured a nostalgic 1980s groove with infectious rhythm and a captivating soundscape, aligning with the group’s retro roots from hits like “Tell Me” and “Nobody”.

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But what truly set this comeback apart was the group’s transition into a band. No longer just dancing, each member took on an instrument: Yeeun on piano, Yubin on drums, Sunmi on bass, and Hyelim on guitar. The process, however, was far from easy.

At the album showcase, the members candidly opened up about the physical and emotional toll of learning instruments. “There was a point where I felt like I hit a wall,” Sunmi admitted. “At first, I improved little by little, but then I hit a plateau, and it got really tough.” Yeeun added, “There were moments when each of us stormed out of the practice room crying.”

Despite the hardships, Wonder Girls pursued this new musical direction with determination. “The biggest question was whether Wonder Girls could be loved without dancing,” Yeeun explained. “Our songs and choreography were what made us popular. I was worried about how the public would receive us as a band. But as the songs came together and we started incorporating movement, I began to feel we could still connect with listeners.”

Wonder Girls

Their efforts paid off. Upon its release, “I Feel You” immediately topped major Korean music charts, claiming No.1 on multiple real-time rankings. It also soared to the top of the Melon Weekly Chart for the first week of August 2015 (August 3rd~9th, 2015), proving that their transformation was not just bold—but triumphant.

Wonder Girls didn’t just change genres; they redefined what it meant to grow as artists in the K-pop scene. Even without Sunye and Sohee, their successful reinvention with “I Feel You” remains a landmark moment in second-generation K-pop history.

Sources: Nate