After singing a hit-soundtrack for the hit-drama Boys Over Flowers, T-Max will this time take part in the soundtrack of the upcoming drama, God Of Study! Their track is titled At Least Once (????), and it is a modern rock style. Like Boys Over Flowers' Paradise, T-Max's track will be G.O.S' main theme song. Fans have got more reasons to anticipate as the soundtrack producers of the hit-drama You're Beautiful took part in T-Max's track. Composer Kim Jae Yang, who composed Lee Hong Gi's track Still (???), composed T-Max's track while Han Sung Ho, who composed Park Shin Hae's Without Words (?? ??), wrote the song's lyric. T-Max's agency Planet 905 stated:

The stories of 'Boys Over Flowers,' 'You're Beautiful' and 'God Of Study' are the same as they are all about teens' success, hope and love. They [T-Max] were able to take part in the OST of one of the most anticipated drama, God Of Study. We hope that T-Max's song once again will help out God Of Study's success and popularity.