District Attorney Stephen Pettijohn returns to his alma mater to lecture on circumstantial evidence, and uses a recent case,the murder of banker James Gardner, to make his point: Constance Gardner had wed James to spite Ted Farnsworth. Later, the pair drove to Gardner's country lodge to urge him to give Constance a divorce. He refuses and that night he is found dead with a bullet in his head. Pettijohn finds that all evidence points to Harry Beach, and the latter is convicted and sentenced to die.