The album contains five songs, including the single "Secret Garden".

[1] On October 30, 2017, WM Entertainment confirmed that due to continued health issues, it was decided that JinE's contract would be terminated so she would officially depart from the group.

[2] The following day, Oh My Girl's agency confirmed that a new mini album was planned for a November release.

[3] In November, it was announced that the released would be delayed to January for "a goal of a more complete album".

[4] On December 23, 2017, WM Entertainment announced Oh My Girl's comeback for January 9, with their fifth EP entitled Secret Garden.