A shy math teacher time-travels back to high school to win his lost love, competing with his younger self for her heart.
Kang Shin-Woo
Young Kang Shin-Woo
Han Ji-Soo
Shin Joo-Hwan
Baek Na-Hee
Jang So-Ra
Choo Geun-Deok
Shin-Woo's mother
Kim Yun-jeong
Mozart student's Head Teacher
Kim Min Seok
