In a dystopian future devastated by air pollution, the survival of humanity depends on the Black Knights — and they’re far from your average deliverymen.

A fusion historical drama that combines romance and legal heroes, and contains a fictional story based on the motif of Gyeongguk Daejeon.

Top actor Ji Eun-ho hires ghostwriter Seo Jung-eun to write his autobiography. Eun-ho is tense, irritable and difficult to work with, but Jung-eun finds her assignment fascinating because Eun-ho claims he began acting not because he wanted to become a star but because he thought being in the limelight would help him find his first love, Ji Eun-dong. Eun-ho and Eun-dong's complicated romantic history has spanned two decades, and he's convinced that he can never love anyone else. As Jung-eun helps him remember Eun-dong and why he lost her, Eun-ho (whose birth name is Hyun Soo) looks back on his memories of her, from when he met when he was seventeen.

Tae-Sik is a widower with a mysterious past. When a young girl he befriends is kidnapped by a vicious drug gang, Tae-Sik rushes to save her.