Joseon's top detective Kim Min attempts to track down those responsible for circulating massive amounts of counterfeit silver bullion in Joseon. He also tries to find the missing sibling of a young girl.

An older brother is a washed-up boxer. His younger brother is a genius pianist with physical disability. The brothers make up through their mother who is full of stories of her past.

The veteran detective Seo Do-cheol and his team at Major Crimes, relentless in their pursuit of criminals, join forces with rookie cop Park Sun-woo to track down a serial killer who has plunged the nation into turmoil.