Chicago, January 1933. Ness and his men turned their big guns on Mikhail "Red Mike" Probich who had hard-fisted his way up from the docks to a position of prominence in the Chicago underworld. They raid a speakeasy/brothel owned by Probich, and run by Connie LaVerne. At the trial, Probich is represented by his crooked lawyer Morton Halas, who grew up in poverty. The trial drags on for 5 days. Finally, Ness is ready to call the last prosecution witness, Connie LaVerne, who "is 80% of their case." Morton Halas objects, on the grounds that a wife cannot be forced to testify against her husband. How long have Probich and Connie been married? About a week. Morton Halas specialized in getting crooks off on a legal technicality, a loophole--chalk another one up for the shyster. Ness tells Halas he'll lock him up someday.
Just then Whitey Metz tells Halas that Larry Coombs, a former acid man for Bugs Moran, wants to see him, pronto. Over at his place, Coombs shows Halas a bottle of Gray Stag booze, the Capone label; Coombs is building a plant to supply Nitti with all he needs. Coombs wants Halas to work for him exclusively; Halas says he already has a client. Coombs tells Halas that Probich is dead. When did he die? Tomorrow night. And so Whitey rubs out Probich with a shiv in the back, and for good measure Coombs gives him 4 slugs in the pump. Unfortunately for Coombs and Whitey they leave an eyewitness to their crime. Ness goes to Coombs and serves him and Whitey with arrest warrants-- Halas is now defending the guys who croaked his former client.
Ness has the eyewitness in protective custody. An attempt to rub out the witness in the middle of the night fails when Rico shoots the hitman. March 2, 1933. Coombs is on trial, and Halas is his attorney. The jury begins deliberations, and it looks like a conviction for sure. Getting Coombs acquitted seems like Mission: Impossible. What sneaky, underhanded trick does Halas have up his sleeve? Eliot Ness and Morton Halas decide to have a talk, over a game of cards; Halas is munching from his ever-present bag of candy. Halas grew up as a poor kid that never had any candy; all he had was poverty and an alcoholic father who'd beat him whenever he was drunk. Halas became a respectable attorney, through brains and sheer hard work; what a great attorney he could have been. But then he started defending gangsters; Halas tells Ness he made 200 grand last year, Ness says that's a lot of dirty money. Halas tells Ness that everytime he wins in court, it's like putting candy in the mouth of the poor kid he was; he has a habit of munching on candy a lot. The jury returns.
Even though the testimony part of the trial is over, Halas tells the judge he has new evidence to present; for the sake of justice, the judge allows it. Then timid and meek Gus Kleeber, with a heavy German accent, tells the judge that he shot Probich. A mistrial is declared and Coombs is set free. Gus Kleeber is sent to the Cook County jail, awaiting his trial for murder. Ness doesn't buy Gus' story; Ness questions him in jail. Ness says, "You loaded this gun? Break it." He tells a puzzled Gus that means open the cylinder as if to load it. Gus hasn't a clue how to open the gun, he never used a gun in his life. Gus is obviously taking the rap for Coombs, but Ness has to find out why.
Coombs has a brewery with a 10,000 gallon tank; he's gonna turn out 500 cases a day for Nitti. Halas, who is now defending Kleeber, goes to Coombs for the 10 grand that Kleeber desperately needs. Meanwhile, Ness and his men go through Gus' stuff back in his apartment; Lee Hobson finds a letter, but it's in German. They ask the landlady, Mrs. Schonbraun, to read it aloud: "Mein lieber Sohn, ich war in Schwierigkeiten mit die Nazis. Sie haben mich verhaftet. Ich hab mit einem Vermittler gesprochen. Er sagt er kann mich aus den Gefängnis und zu die Grenze bringen." She says the letter's from Berlin, from Gus' father: he was in some difficulties with the Nazis, he's in prison. But he talked to a go-between. His name and address are here, and he can get the father out of prison and across the border for $10,000. Your loving father, Heinrich Kleeber.
With further investigation, Ness finds out Gus has a bum ticker, he won't live more than 6 months. No wonder the prospect of a life sentence doesn't scare him. Even though Kleeber was holding up his part of the bargain, when Coombs finds out Ness is snooping around, Coombs has one of his boys on the inside rub out Kleeber. Meanwhile, one fingerprint at a federal distillery where copper tubing was stolen is all Ness needs to arrest Whitey. Coombs is scared Ness will sweat Whitey about the Probich murder; furthermore, Ness leaks the false story that Kleeber was only seriously wounded, and survived, and will spill the beans about Coombs at his trial. Coombs visits Whitey in jail; Whitey tells Coombs he better do something, because "Ness is gonna tag me for the Probich rap, and I ain't gonna fry alone!"
Ness sets a trap; and he has Agent William Youngfellow, apparently working as a repairman, keep a lookout on top a streetlight pole. On the day of the trial, he has an ambulance drive up to the courthouse, and they have what looks like a man, covered in a sheet, carried on a stretcher towards the court house building. Larry Coombs and his men start blasting, they machine-gun the stretcher (the man under the sheet was a just a lot of blankets.) Ness shoots Coombs; Coombs shoots Halas. Morton Halas, the poor kid who grew up in poverty, and became a crooked attorney--now he was paying the ultimate price for his crooked dealings; because when Death is the judge, there is no Loophole.