On June 26, 2018, a source from Cube Entertainment stated that the group will be making a comeback on July 18 with no further details.
[1] On the same day, the group revealed through a magazine interview that theme for this album will be the collaboration of retro and futurism, resulting in the album's name, Retro Futurism.
They also revealed that they were going to a time where people were using folder phones and pagers, and also were inspired by retro singers.
[2] On July 13, the group revealed the track list through a video on various platforms.
[3] The EP was released on July 18, 2018, through several music portals, including MelOn in South Korea and iTunes for the global market.