In January 2016, D.O. was announced as one of the cast of voice actors for the feature-length animated film The Underdog, which is slated to premiere in 2018. He will voice Moongchi, a stray dog who is separated from his owner. In February 2016, he collaborated with Yoo Young-jin on a duet titled "Tell Me (What Is Love)" for S.M. Entertainment's Station music project. He had previously performed a short version of the song as a solo performance throughout Exo's first concert tour. Later in February, D.O. starred as the male lead alongside Actress Kim So-hyun in the romantic film Pure Love. In October 2016, D.O. starred alongside Chae Seo-jin in Positive Physique, a web drama produced by Samsung. The series became the most watched web drama of all time. In November 2016, D.O. starred alongside Jo Jung-suk and Park Shin-hye in the film My Annoying Brother, playing a national level Judo athlete. D.O. and Jo Jung-suk also recorded the ending theme song, titled "Don't Worry", for the movie. D.O was awarded the Blue Dragon Film Awards a year later for his performance in the film.