Reporter John Randolph assumes his father's position as publisher of the Star Tribune after the elder Randolph is murdered by racketeers. Determined to bring his father's murderers to justice, John campaigns to elect his friend and future father-in-law, William Burnette, to the office of district attorney. With the backing of John's paper, Burnette wins and faces his first case, to bring Randolph's killers to trial. Complications arise, however, when Burnette's informant in the Randolph case is murdered by gangster Joe Draper and clever criminal attorney Whittaker is hired to defend the gangster. Discovering that Draper is John's biological father and the first husband of Mrs. Julia Randolph, Whittaker threatens to expose the family scandal unless Julia steals Draper's confession from Burnette's safe. After Julia refuses, Whittaker hires Clipper, a safe cracker, to steal the document, and without Draper's confession, Burnette is forced to reduce the murder charge to manslaughter. John, who believes that Randolph was his real father, accuses Burnette of accepting a bribe from the racketeers. He also remains doggedly determined to bring Draper to justice, despite the efforts of his mother and his fiancée, Barbara Burnette, to stop him. As Clipper sells Draper's confession to John, Whittaker has his client released on bail, and Draper disappears. To exonerate her father, Barbara decides to steal the confession from John's safe, but when she arrives at his office, she becomes involved in a shootout between Draper and Gordon, a newspaper employee, and as a result, is arrested for Gordon's murder. Knowing that Draper is the only person who can exonerate Barbara, Julia finally tells her son the truth about his father, and John sets out to find him. A tip from Clipper leads him to Draper, and after John informs Draper that he is his son, Draper agrees to write a confession clearing Barbara and implicating Whittaker. Before he can escape, Clipper and Whittaker arrive, followed by the police. Draper dies in the ensuing shootout, but on the basis of his signed testimony, Whittaker is convicted and exposes the gang's ringleaders.