February 1, 1933. Late that night, John "The Cropper" Cropsie, the enforcer for Jules Flack (boss of the Westside combine), stands in the back alley behind the Lido Burlesque house, by the stage door entrance, pumping several slugs into David Alpine, the key booze supplier for the combine who had been selling to the competition. On the night of February 2, Eliot Ness is having Cropsie reenact the crime in front of an eyewitness to the shooting Belle Alpine, David Alpine's widow. Ness asks her if she can identify him as the man who shot her husband. Belle walks up to Cropsie, slaps him across the face, and then blatantly lies to Ness that she never saw him before in her life.
With the repeal of Prohibition just around the corner, Jules Flack is getting ready for the big switch and is going to concentrate on narcotics. Flack wants to convert his assets into a couple of million bucks so he can throw in with Luciano. Cropsie, who had been Flack's Enforcer for thirteen years, wants in on the business. Flack throws him a bone by offering to let him fill in for Lefty Gorman, a small-time collector, who is in the hospital. While Cropsie is shaking down a customer, who owes 12 bucks, he finds out that the guy's a chemist for the Pyramid Solvents Corp. The company has just made 50,000 gallons of denatured alcohol, manufactured under federal license for industrial use. Cropsie doesn't want to be just a nickels-and-dimes collector for Flack. He has dreams of making "One Last Killing" before repeal.
That night, Murray Alpine, along with his pal Phil Olive, start to take Cropsie for the infamous "one way ride" for rubbing out David, Murray's cousin. But Cropsie tells them about the 50,000 gallons of alcohol, which at 20 bottles per gallon is a million bucks worth. Murray and Phil figure why rub him out for nothing, when they can split a million bucks 3 ways? So forgetting about David's death they become partners. And so Cropsie, Murray, Phil and Pat the safe-cracker go to the office of Pyramid Corp., ostensibly to crack the safe with an acetylene torch. But while they take four hours doing this, their gang takes truckload after truckload of 5-gallon cans of alcohol from the place, dumps the alcky into vats, and then returns the cans, having refilled them with water. 50,000 gallons of alcohol stolen, and Pyramid Corp. doesn't even know it...yet.
Ness is watching Flack's every move. Flack converts his booze to cash and sells thirtytwo of his speaks to a restaurant chain, trying to raise money so he can tie in with Luciano. Even though Flack is getting out of the booze racket, Cropsie has a meet with Flack to sell him the alcohol. Cropsie wants $1-million and Flack counters with $100,000. Cropsie says 50,000 gallons is 200,000 quarts, which he will cut to 500,000, at $6 a quart, that's $3-million. Flack says he can only get $3 a quart. Ness and his men investigate the Pyramid Corp. Enrico Rossi accidentally knocks over a stack of 5-gallon cans stacked about eight feet high and almost crushes Lee Hobson. But some cans spill their contents revealing that it's not alcohol but water.
Cropsie has the alcohol stashed at a the old brewery. Ness figures Flack is the only one big enough to buy all the alcohol so he calls Flack to his office, and gives him a sheet of paper with the formula for removing the de-naturant. Ness tells him that's the only safe way to purify the stuff. Ness doesn't want the wholesale poisoning of Chicago on his conscience. But Cropsie double-crosses Murray and rubs him out.
Saturday, March 4, 1933, Flack agrees to pay $175,000 for the booze and will put the money in the night deposit at Yardmen's National Bank, where Cropsie has an account. But there's a hitch...Cropsie doesn't know that the old brewery is owned by Belle Alpine!
Belle wants $100,000 and Flack says it will come out of Cropsie's share. Later, Cropsie double-crosses Flack, by phoning a tip to Ness where the booze is, and when Flack will pick it up. Monday, March 6, 8:45 a.m. Olive takes Flack and his boys to the old brewery. Ness and his men show up. In the shootout, Flack and his boys get it. Enrico is especially good with his chopper. At 10 a.m., Cropsie wants to collect his loot from the bank but that bank, like every bank across the country, is closed by order of FDR, who just got inaugurated. Cropsie tells Ness he's got nothing on him, but Ness informs him that Belle just remembered that Cropsie shot her husband. The Cropper is arrested, a victim of bad luck and timing.