Do Kyung-soo, better known by his stage name D.O., is a South Korean singer and actor. He is best known as a member and one of the main vocalists of the South Korean-Chinese boy group EXO and it's sub-unit EXO-K. Apart from his group's activities, D.O. has also starred in various television dramas and movies such as Pure Love (2016), My Annoying Brother (2016), Positive Physique (2016), Room No.7 (2017), 100 Days My Prince (2018), Along with the Gods, and Swing Kids (2018). Kyung-soo began singing in primary school and was an avid participant in local singing competitions throughout his high school career. In 2010, he was advised to audition for SM Entertainment after winning a local singing contest. He subsequently became a trainee during his last two years of high school. Kyung-soo was formally introduced as the eighth member of EXO on January 30, 2012. In September 2014, Kyung-soo made his acting debut with a supporting role in the movie Cart, playing a high school student and son of a grocery store worker and union member. Later in 2014, D.O. made his small screen debut playing a supporting role in the SBS drama It's Okay, That's Love, which starred Gong Hyo-jin and Jo In-sung. Kyung-soo was praised by film critic Heo Ji-woong for his performance in the series, and was later nominated for the Best New Actor award at the 51st Baeksang Arts Awards. In November 2016, Kyung-soo starred alongside Jo Jung-suk and Park Shin-hye in the film My Annoying Brother, playing a national level Judo athlete. Do Kyung-soo was awarded the Blue Dragon Film Awards' Best New Actor award a year later for his performance in the film. In 2018, he was cast in his first small-screen leading role, playing a crown prince in 100 Days My Prince. The series was a commercial success, becoming the fifth highest-rated Korean drama in cable television history. Do Kyung-soo was awarded Most Popular Actor at the 55th Baeksang Arts Awards. Do Kyung-soo enlisted for his mandatory military service, serving active duty on July 1, 2019, and will finish his service in January 2021. He posted a handwritten letter on EXO's official fan club following news of his plans to voluntarily enlist. The same day, he released a solo track which he co-wrote, "That's Okay", through the SM Station project.