In 1929 Chicago, Federal investigator Eliot Ness struggles in the fight against Al Capone. He decides to form a special team of reliable, dedicated, honest law enforcement officers.

Eliot Ness is lured south of the border to retrieve a witness who will help his case. Only it's a set-up...once there, the mobster on trial is planning to have Ness killed.

Spring 1931. Gangland warfare had broken out again with sudden violence in the streets of St. Louis. Tim Harrington, who was long entrenched as the undisputed boss of the city, was fighting off the challenge to his leadership from Joe Courtney, an upstart hoodlum. The elder Dink Conway calls for a sit-down between the two, at the Jockey Club. Dink points out they are operating the old way: shootouts and dealing in cash. He offers them organization and protection, and says the new way is to use fronts to cover your criminal activities and keep books so the Feds can't get you on income tax evasion (he knows what happened to Al Capone).

Chicago, 1931. Eliot Ness and his men had cracked the bootleg empire of Al Capone, by smashing his breweries and speakeasies.* But now, thousands of gallons of alcohol were coming into the city from an outside source. Ness meets with D.A. Beecher Asbury; it doesn't take Sherlock Holmes to figure out where the booze is coming from, they've found 5-gallon cans with ""Brawley Mills, Brawley, New York"" stamped on them. Chemical analysis showed the stuff is 190 proof, no doubt produced under U.S. Government permit-- but it contained no denaturant, so it is safe to drink.

1934. Prohibition had been repealed (the Volstead Act ran from January 17, 1920 - April 7, 1933). The syndicate was looking for new sources of revenue. Frank Nitti expands his empire, and goes after small theatres-- with his extortion racket. Late one night, after theatre owner Harold Coldman had refused to pay, Nitti has his triggerman Louie Campagna throw some acid into Coldman's face, blinding him. Eliot Ness and his men are on the case-- this is only the latest in a series of muggings and beatings; even a theatre was burned down. Ness knows if he lets Nitti get away with extorting the small, independent theatre owners, in a few months Nitti will go after the big chains.

Ring of Terror-- Boxing ring, that is. July 1931, the Chicago Sports Arena was like a hundred other boxing rings across America-- a place where young toughs from reform schools and rotting tenements, willing to sacrifice their blood, could try to rise above the oppression of poverty. But the young men with the boxing gloves only got a small amount of the money; the big payoffs went to the gangsters.

In the summer of 1934, a new gambling device was sweeping the nation: the punchboards. Even though they were nickel-and-dime games, it added up-- they made more money for the mob than the numbers racket. After Ness and his men smash some of the punchboard manufacturing sites, the 5 members of the syndicate running the punchboards hold a meet at a building by the freight yards: the top mobsters from Chicago (Jake ""Joe"" Petrie), Cincinnati, St. Louis, Detroit and New York (Max Riegel).

Petrie says he can sum up all their problems in 2 words: Eliot Ness.

Chicago, April 16, 1934. Prohibition is over, the main racket is now narcotics. The New York Syndicate, the ""Big 6"" send their representative Wally Corbin to Chicago, to pick up a shipment of heroin from Louie ""The Bear"" Madikoff-- he's the top dealer in the Midwest and the chief supplier of the NY Syndicate. Ness has already picked off 2 of Madikoff's runners. Wally picks up 1-1/2 kilos of the junk, worth $200,000.

Chicago, 1929. Mike Brannon's been a cop for 15 years, but now he's being suspended for hospitalizing ""one of Tony Lamberto's dope-pushing punks."" Mike thinks Captain Bellows is corrupt for not going to bat for him. There is a tense moment when the Captain asks for Mike's gun-- Mike points it at him. But then, Mike turns the gun over and leaves.

June 1930. Speak owner Louie Akers-- about to go dry and out of business because Guzik couldn't supply him with hooch for that last 3 weeks-- buys his booze from another supplier. Akers pays Johnny $1,142 for barrels of beer and crates of whiskey, that some deliverymen just dropped off. Just then, a couple of Guzik's boys (Sully and Mac) drive up; they start blasting at the delivery truck (which still has plenty more booze in back), just as it's pulling away.

Chicago, Spring 1931.  That night, Ness and his men are in their car; it's an 80 mph chase to catch a guy running whiskey for Solly Girsch.  The 19-year-old driver has a high-speed accident; his car overturns and explodes in flames.  Solly Girsch is the king of bootleg whiskey; he has 500 ""mom & pop"" stores pushing his hooch-- all together, they form the biggest single outlet of whiskey in Chicago.