The movie opens in 1930. Eliot Ness (Kevin Costner) has just been assigned the Capone case and has arrived at his office in the Chicago Police Department full of righteous indignation and grand aspirations. Ness is a straight-shooter who believes that the law, whether good or bad, is paramount. He may not agree with prohibition, but, as long as that's the way the law is written, he will defend it, and that means getting Capone (Robert De Niro) off the streets. One of Ness' early liquor raids is a failure, and it turns him into a front-page laughingstock. However, instead of causing him to turn tail, it stiffens his resolve.