Jung Se Ro is a hardworking young man who works multiple part-time jobs while studying for the foreign civil service exam. His father is a petty criminal and a con man, and their family lives a transient life because of his deals, currently staying in Thailand.
Despite wanting an honest life for himself, Se Ro's dreams are shattered on the night of a glamorous jewel exhibition opening in Bangkok. His father dies in an incident involving stolen diamonds, and because Se Ro was at the scene when another man was shot, he is accused and arrested for murder. After spending five years in a Thai prison, upon his release he takes up a new identity and becomes a con man just like his father. He joins a ring of jewel smugglers led by Park Kang Jae, with whom he shares a brotherly bond. Kang Jae was raised like a son by Se Ro's father, who taught him all the tricks of the trade. But Kang Jae has harbored a lifelong jealousy towards the real son, which is stoked further when the woman he loves, smuggling accomplice Seo Jae In also falls for Se Ro.
Then Se Ro meets Han Young Won, the cold-hearted heiress to a jewelry brand. She was madly in love with her fiancé Gong Woo Jin, and had closed herself off after his death. But Se Ro draws her out into the world, while Young-won gives him a reason to live when he had all but given up. They fall in love, not knowing that the man Se Ro was accused of killing had been Young Won's fiance. His love for her becomes his punishment, but also his salvation.