In 2014, Lee appeared in the music video of labelmate
Hong Jin-young's song "Cheer Up". On April 12, 2015, she debuted as a member of Music K Entertainment's new girl group The Ark under the stage name "Halla". The group released one single, "The Light", before going on hiatus. In March 2016, it was unofficially announced that the group had disbanded a month before. On April 26, 2016, Lee joined the auditions for
The Idolmaster KR, a Korean drama loosely based on the Japanese raising simulation and rhythm video game series
The Idolmaster, where she played the main lead and her twin sister. On November 4, 2017, Lee joined
The Unit: Idol Rebooting Project. She won a final spot on Top 9 and became a part of the group called
UNI.T. == Personal life ==