特警小组长官Danny Waldron在一次行动中击毙了一名犯罪嫌疑人，他和队员一致声称此举是出于自卫，但反腐小组AC-12的主管却认为这是一起蓄意杀人事件。随着调查深入，更多意想不到的真相浮出水面……

Colorado Springs, late 1970s. Ron Stallworth, an African American police officer, and Flip Zimmerman, his Jewish colleague, run an undercover operation to infiltrate the Ku Klux Klan.