Chicago, January 1933. Danceland has a big sign, ""30 girls, open until 2 a.m."" Inside, customers mingle with the dime-a-dance girls. Hoofer Ellie Haskell says goodnight to the owner, Marty Pulaski; outside, she is immediately shot by a sniper on the roof of a building across the street-- the sniper is Herbie Pulaski, Marty's mentally disturbed brother. Lt. Roy Gunther is on the case, he questions Marty, who has 20% of the dancing racket. However, Marty is sure his main competitor, Vince Bogan who owns 80% of the dance racket, is responsible for the killing; Marty phones Bogan and threatens to rub him out. Back at Ness' office, Lt. Roy Gunther discusses the case with Eliot. Ness has to go to New York to testify before a grand jury, he'll be gone a week-- he puts Lee Hobson in charge. Marty has his brother Herbie drive him over to Bogan's place; inside, Marty shoots Bogan. Outside, when Herbie hears the shots, he reaches for his rifle in the trunk of the car-- and has a flashback (thetvdb.com)