Lee Yong-Ju Director, Screenwriter Uhm Tae-woong Present Seung-min Actor Han Ga-in Present Seo-yeon Actor Lee Je-hoon Past Seung-min Actor Bae Suzy Past Seo-yeon Actor Jo Jung-suk Nab-ddeuk-yi Actor Yoo Yeon-seok Jae-wook Actor Kim Dong-joo Seung-min's Mother Actor Kim Eui-sung Professor Kang Actor Lee Seung-ho Seo-yeon's father Actor Park Soo-young Director Gu Actor Cho Hyun-chul Dong-gu Actor Go Joon-hee Eun-chae Actor Shim Jae-myung Producer Lee Eun Producer Kim Gyun-hui Producer