Twelve people who served on the jury during a trial that sent a man to prison for murder one year earlier are assembled in a lonely house on a stormy night. The guests have been summoned to the house by the convicted man's attorney, J. E. Burton, who tries to convince them that they had erred in their verdict because they based their decision on circumstantial evidence. In order to convince the former jurors to sign a petition asking the governor to pardon his client, Burton shows them how easy it is to accuse the wrong person of a crime by staging an elaborate murder scheme in which one of the jurors is framed for killing his assistant. After realizing their folly, the jurors agree to sign the petition, and the imprisoned man's freedom is secured.