: At the suggestion of senior prosecutors, Yo-han goes undercover into Seongju Prison to gather evidence against a corrupt gambling ring and a high-ranking prosecutor.
(Lee Yoo-young): An ambitious businesswoman who assists Yo-han for her own vengeance. : At the suggestion of senior prosecutors, Yo-han
The series revolves around , a meticulous judicial trainee who lives with his grandmother. : At the suggestion of senior prosecutors, Yo-han