Twin brothers Woo-sin and Suh-yeon lose their father in a murder case. Twenty-two years later, the brothers seek to clear their father's name.

On assignment in a perilous city to inspect a Black Ops team and its notorious leader, an upstanding prosecutor steps into a deadly war between spies.

During a mock trial at school, a student makes a shocking discovery. Yang Jong Hoon, a former prosecutor-turned-professor, examines the crime scene.

It follows the lives of employees at Incheon International Airport.