The protagonist takes the fall for his girlfriend, going to prison, unaware that the person his girlfriend and a wealthy heir accidentally killed was his own older brother. To make matters worse, his girlfriend had already betrayed him, secretly involved with the heir. Regretful and heartbroken, the protagonist inherits the legacy of a powerful, secretive organization while in prison. The disciples of this organization include influential businessmen, aristocrats, officials, and mafia bosses. He becomes the new leader.
Upon his release, he learns that his father has died from grief, leaving only his widowed mother, younger sister, and sister-in-law behind. At his father's funeral, the heir causes trouble, intending to dishonor his sister-in-law and younger sister. The protagonist fights back, driving away the criminals. Despite his family's misunderstanding, he uses the power of his inheritance to bring his father back to life.
At a major family celebration of the heir's family, the protagonist storms in with his brother's coffin, defeating their numerous martial experts. He avenges his brother and settles his own score, but there are still powerful figures behind the heir's family. Afterward, his own family is targeted by a criminal group seeking to extort them and dishonor his sister-in-law. The protagonist saves his family, then faces challenges involving his sister's workplace bullying and a series of medical incidents with a prominent family head. Through these trials, he earns his family's respect and becomes the true leader of the secretive organization.