"Monster" is a song recorded by South Korean boy band Exo for their third studio album Ex'Act. It was released in Korean and Chinese versions by SM Entertainment on June 9, 2016 as the second single for the album.
Written and composed by Kenzie and LDN Noise, "Monster" is described as a "dark and intense" medium-tempo dance song with lyrics about a man's "excessive fixation on his lover". The song served as one of the "double title tracks" for Ex'Act, the other being "Lucky One", and was released together with the album on June 9, 2016. Exo began performing the song on South Korean music TV shows on the same day.
The Korean and Chinese music videos for "Monster" were released one hour after the song itself. Apart from Exo's performances of the song at various settings, the videos also depict the members as rebels that were eventually captured but ultimately released from a prisoner transport vehicle by Baekhyun, who has been disguised as the driver. The Korean version was the fourth most-watched K-pop music video on YouTube in 2016. An additional music video exclusively showcasing the song's choreography was released on June 15, 2016.
On June 8, 2018, the Korean music video exceeded 200 million views on YouTube, becoming their first music video to do so.