Prosecutor Hwang Si-mok (Cho Seung-woo) lacks empathy after brain surgery but is sharp in solving crimes. While investigating a murder, he teams up with Police Lieutenant Han Yeo-jin (Bae Doona). Their search for the truth leads them to uncover a deep-rooted corruption scandal between the Prosecutors' Office and a powerful chaebol, but their efforts are constantly hindered.

"Uncover the truth, no matter how deep the corruption goes"