Lee Joon

Ahn Joong-hee (36)— He is an idol-singer turned actor at Gabi Entertainment and the real Byun Han-soo's son. He lived in the U.S before moving to Korea to become an idol. Although he is an actor, he could not really act well which caused him to miss out on opportunities on doing more popular acting jobs like a mini series. After finally being cast on one, he decided to move with the Byuns/Lees, to know what it is like living with his "father", to help him with his acting. Living with the Byuns/Lees actually improves his acting skill and his image so much that he becomes famous again. He later starts to fall for Mi-young which causes him to believe that he is crazy because she is supposed to be his half-sister. He struggles with his feelings for Mi-Young and his anger at her father for posing as his father and betraying his trust. Eventually, he learns to forgive Yoon-seok and his wife Young-sil for their betrayal as he understands their reasons and he also has grown to love the family like his own. He also gets together with Mi-Yeong and they become engaged at the end of the series.

Yoon San

Ma Seok-woo

Han In-sang (18)

Fama, idol singer investigated for propofol use (ep. 19)

Choi Dae-han

Ryu Tae-oh, an inmate of a prison psychiatric hospital, who becomes a barista after his release. With a genius IQ of 150, his excellent and detailed memory may prove valuable to cracking the case, but he also happens to have the disposition to be a dangerous psychopath, and considers Gap-dong his god and hero.

Yoon Shi-hyuk

Passerby (ep 1)

Yeo-chi's boyfriend (cameo, ep 1)

Ahn Ba-woo