The music video for "Day by Day" was directed by Cha Eun-taek in Seoul, South Korea. It was announced on June 12, 2012, as a 20-minute music video drama starring the group themselves in a science-fiction setting; reminiscent of the movie Mad Max. A large amount of work was needed to complete the computer graphics featured in the video, which caused its release to be delayed by 13 hours.
