A lawyer, caught up in a murder case, becomes a notorious and genius con artist overnight, in order to fight against a huge conspiracy and survive.

Set during the turbulent time of the fall of Goryeo and the founding of Joseon, two former friends face-off against one another over a woman and the future shape of the nation.

Lee Young-Joon's family runs a large company and he works as the vice-president of the company. He is smart, rich and handsome, but he is arrogant. His secretary is Kim Mi-So. She has worked for him for years and she is perfect for him, but Kim Mi-So decides to quit her job.