Ji Sung

Kang Yo-han, a chief judge who punishes the dishonest with no mercy, thus earning himself a reputation as a hero of the people. However, he maintains a mysterious background and conceals his true motivations and ambitions. Moon Woo-jin as child Kang Yo-han

Cha Yo-han / John Cha Park Shi-wan as young Yo-han

Cha Joo-hyuk

Park Jung-woo

Shin Suk-ho

Cha Do-hyun (Cha Joon-young) Lee Do-hyun as child Cha Do-hyun (Cha Joon-young)

Jo Min-hyuk

Cha Ji-heon: A spoiled heir of DN group, known to be immature and hold grudges. He quickly falls in love his secretary, Noh Eun-seol though the latter is initially confused and not accepting of his advances. They date then eventually get married after a series of comedic events at the end of the series.

Han Ji-hoon - He has a tragic past that he doesn't remember, yet he overcomes his underprivileged childhood and becomes a competent prosecutor. He joins JK Group and sacrifices his all to help In-sook become the head of the conglomerate because he considers her his saviour.

Kim Su-ro Park Gun-woo as young Kim Su-ro

Lee Eun-sung

Kim Woo-jin/Seok-jin (episodes 9-10)

Choi Jung-won Go Dong-hyeon as young Jung-won

Oh Joon-soo, Hyo-dong's friend