Jang Keun-suk
Because the drama features a concert footage of A.N.JELL in it, the cast members actually performed a mini-concert, where it was reported that as many 25,000 fans showed up. The group performed the songs "Promise" and "Still". Jang Keun-suk also sang "Good Bye" and "What Should I Do", the latter is the track Tae-kyung remakes for his mother in the drama. Park Shin-hye sang her character's theme song, "Lovely Day".