Along with the members of 2PM, 2AM appeared on the documentary Hot Blood, which documented their rigorous training program. Changmin was the only member of One Day to not appear in the documentary. He was serving in the military at that time. 2AM’s leader, Jo Kwon, holds the record as the longest trainee in JYP Entertainment, having completed 2567 days of training.
2AM made their debut performance on KBS Music Bank performing «This Song,» (이노래) which talks about a man who has nothing left to offer his love except for one song.
1st Single «This Song»
2AM’s first single «This Song» came out on and debuts on KBS Music Bank on July 11, 2008. This single contains the title song, «This Song,» «Not Because,» and the follow-up song, «What Do I Do.»