Jo In Sung as Jang Jae Yul
– Sung Yoo Bin as Jang Jae Yul (young)
Gong Hyo Jin as Ji Hye Soo
– Kang Joo Eun as Hae Soo (child)
Lee Kwang Soo as Park Soo Kwang
Sung Dong Il as Jo Dong Min

Supporting Cast

Jin Kyung as Doctor Lee Young Jin (Dong Min’s ex-wife)
Lee Sung Kyung as Oh So Nyeo
Yang Ik Joon as Jang Jae Bum (Jae Yul’s older brother)
– Noh Tae Yub as Jae Bum (young)
D.O. as Han Kang Woo
Cha Hwa Yun as Jae Yul’s mother
Kim Mi Kyung as Hae Soo’s mother
Yoon Jin Yi as Lee Pul Ip
Do Sang Wooas Choi Ho
Choi Seung Kyung as Oh Do Deuk
Baek Seung Do as Hwan Hee
Tae Hang Ho as Yang Tae Yong
Jang Ki Yong as Sam
Lee El as Se Ra
Lee Dong Ha as Yoon Chul
Moon Ji In as Min Young
Choi Moon Kyoung as Ji Yoon Soo (Hae Soo’s older sister)
– Lee Chae Mi as Ji Yoon Soo (young)
Choi Dong Goo as Patient

Cameo

Goo Ha Ra as Jae Yeol’s fan
Heo Ji Woong