Mistaken identity or delicious deception?

Sultry blonde Barbara Lacey saunters into the Night and Day, a St. Louis bar, where she waits hours to deliver a mysterious envelope to a man that never appears. She reluctantly entrusts it to bar owner Alfie Greenblatt, and steps into the alley. Moments later Alfie hears the crisp pop of a bullet. He calls Sergeant Reggie Combs to investigate. Was Barbara's death an accident, or murder?

Helen Tattaglia approaches her neighbors Elvin Suggs and his partners Cobra Glynes and Dimond "Di" Redding of the Grapevine Detective Agency. She hires them to trail her "abusive" husband; she also suspects her in-laws, who live across the street, have arranged for her murder. The detectives are skeptical but they accept the case. They soon discover Helen's sordid past, including another woman named Barbara Lacey.

Frustrated with the case, Detective Reggie Combs turns to his friends at the Grapevine Detective Agency for help. The shady dealings of the Tattaglia family begin to unravel, while they reveal the secret in the envelope.