The story begins in the 1960s. Lee Ki-chul (Lee Jong-won), a student movement leader, came to a remote mine to atone for his sins and became a miner. In the process of fighting against the greedy and sinister mine owner Shin Tae-hwan (Cho Min-ki), Lee Ki-chul fell into the latter's trap and died. Lee Ki-chul's eldest son Lee Dong-chul (Song Seung-heon) witnessed all this. In grief, he vowed to avenge his father. At the same time, nurse Mi-ae switched the children of Shin Tae-hwan and Lee Ki-chul in order to avenge Shin Tae-hwan's abandonment. In this way, Shin Tae-hwan's child Myeong-hoon (Park Hae-jin) became Lee Dong-chul's younger brother, and Lee Ki-chul's son Lee Dong-wook (Yeon Jung-hoon) grew up under Shin Tae-hwan's knees. As time went on, when Myeong-hoon and Lee Dong-wook's complicated life experiences gradually surfaced, the life trajectories of the two were distorted.