When gangster Nick Moses and another Chicago mobster threaten to go to war after Moses poaches customers in the other's territory, Frank Nitti - now the top mobster in Chicago after the recent incarceration of Al Capone for tax evasion - tells them to settle things amicably, or else. Moses pretends to make amends but actually arranges a hit on his rival, one that also leads to a young newspaper boy being shot. When Nitti tells him he's a dead man, Moses tries to make one last deal - in return for sparing his life, he will make sure Eliot Ness is killed.

Lily Dallas is a highly intelligent ex-con who has a history of committing bank robberies. This time she and her husband George 'Blackie' Dallas, who is known for his deft use of a Tommy gun, kidnap a well known and very rich businessman Thomas B. Randall and demand $300,000 ransom. Mrs. Randall follows their instructions and doesn't contact the police until after she has paid the ransom so Ness puts out a rumor that all of the bills have been marked.