Kim Myung Soo, known by the stage name L, is a South Korean singer and actor who debuted as a member of the boy band INFINITE in 2010 and its subunit INFINITE F in 2014. Kim attended Duk Soo High School and graduated from Daekyung University on February 15, 2013, majoring in practical music and and received along with members Kim Sung-kyu, Sungyeol, Hoya, and Dongwoo the 'Proud Daekyung University Student Award' in hopes that the group would continue to grow and bring prestige to the school.
In 2011, he made his acting debut in Japanese drama Jiu Keishicho Tokushuhan Sousagakari, which aired on TV Asahi in July. On May 15, 2013, L released a photo essay book titled L's Bravo Viewtiful, showing photos taken by him on a 93-day journey. The book was a best-seller and reached #1 in pre-orders on online bookstores such as YES24 and Kyobo. He has meanwhile published a second photo book.
On August 18 2019 L's contract expired with Woolim Entertainment. Woolim Entertainment announced that L would not renew his contract with the company, but he will still be a member of INFINITE. In 2020, he signed with the agency Management 2sang.
On February 22, 2021, L enlisted for his mandatory military service as a member of the Republic of Korea Marine Corps. Before his enlistment, he released his debut single album Memory on February 3., 2021. He officially discharged from the military on August 22, 2022.
On March 7, 2023, it was announced that he has signed with Look Media.