1the9 (Hangul: 원더나인, stylized as 1THE9, pronounced as Wonder Nine) was a South Korean boy band formed through the 2018 survival competition Under Nineteen. The group was composed of 9 members: Yoo Yong-ha, Kim Tae-woo, Lee Seung-hwan, Shin Ye-chan, Kim Jun-seo, Jeon Do-yum, Jung Jin-sung, Jeong Taek-hyeon and Park Sung-won. The group's debuting members were announced on February 9, 2019 and was initially slated to be promoting under PocketDol Studio for 12 months. After delays surrounding the COVID-19 pandemic, the group disbanded in August 2020.