1TEAM (원팀; known pre-debut as TEAM LWZ (팀라웍즈)) is a five-member boy group under Liveworks Company. They debuted on March 27, 2019 with their first mini album Hello!.
BC and Rubin had experience in the music industry prior to debut. BC was a former member of the boy group I-REX until its disbandment. He was also a former contestant on the idol survival reality show, BOYS24, and was a member of their pre-debut boy group of the same name. He later went onto another idol survival reality show, MIXNINE, but was eliminated.
Like BC, Rubin was also a former contestant on the idol survival reality show, BOYS24, a member of BOYS24, and also participated on MIXNINE, but unlike BC, he made it into the top 9 ranks to debut. However, their debut was cancelled due to disagreements with contract lengths between YG Entertainment and the trainees’ individual companies.
On December 17, 2018, Liveworks Company released profile images and interview videos of the members for their upcoming boy group, then known as TEAM LWZ. Another set of photos was released on December 24.
Liveworks announced on March 4, 2019 that the group will make their debut on March 27 under the name 1TEAM.
Source: kpop wiki