1THE9 (원더나인) is a nine-member project boy group signed under MBK Entertainment and managed by PocketDol Studio. They were formed through the competition reality show Under Nineteen and officially debuted on April 13, 2019 with their first mini album XIX.[1]

The group is under a 17-month contract; 5 months of training before promoting for 12 months.[2]


Pre-debut: Under Nineteen

2019–present: Debut

On February 26, the debut date was set to April 12, 2019 (later changed to the 13th). On the same day, the concept photos of the members was revealed.[3][4]

On April 5, the debut timeline started and the name of the album was revealed to be XIX with the title track being "Spotlight". A pre-debut title track, "Domino", which was written and produced by Under Nineteen's vocal trainer Crush, was released on April 7. The group then made their official debut on April 13 with the release of their debut mini album XIX.

On April 17, they held their debut showcase through V Live, with their fandom and fandom color announced to be Wonderland and Lime Punch, respectively.[5]


Name Position(s)
Jeon Do Yum (전도염) Main dancer, lead rapper, vocalist, center
Jung Jin Sung (정진성) Main dancer, lead vocalist, visual
Kim Tae Woo (김태우) Vocalist, rapper
Shin Ye Chan (신예찬) Main vocalist, lead dancer
Jeong Taek Hyeon (정택현) Main rapper, vocalist, face of the group
Yoo Yong Ha (유용하) Leader, lead rapper, vocalist
Park Sung Won (박성원) Main rapper, vocalist, maknae
Lee Seung Hwan (이승환) Lead dancer, lead vocalist
Kim Jun Seo (김준서) Lead vocalist, lead dancer, rapper, visual


Mini albums

Digital singles



Official links

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