Newspaper reporter and amateur ham radio operator John Keefe, anxious for a scoop, plants a shortwave radio in the courtroom to eavesdrop on the grand jury's investigation into the brokerage house owned by Anthony Pelton and Thomas Reedy, which is allegedly dealing in fraudulent stocks. When the story breaks in the newspaper under John's byline, John's brother Michael, the assistant district attorney, is castigated by his boss. Nevertheless, John continues to jeopardize his brother's career and decides to infiltrate the brokerage house by posing as Avery, a wealthy young investor from the South. In a meeting at Pelton and Reedy's office, John leaves behind his briefcase, which has a microphone concealed in it. Soon afterward, Pelton, who has become squeamish over the grand jury investigation, decides to skip town. While emptying the safe, Pelton is accosted by a gun wielding young man, and in the ensuing skirmish, the gun discharges into John's briefcase.