The drama depicts a jury forced to reconsider its nearly unanimous decision by the single dissenter who sows a seed of reasonable doubt. The story begins after closing arguments have been presented in a homicide case, as the judge is giving his instructions to the jury. The twelve men must unanimously decide on a verdict of 'guilty' or 'not guilty'. The case at bar pertains to whether the young man murdered his own father. The jury is further instructed that a guilty verdict will be accompanied by a mandatory death sentence. The twelve then move to the jury room, where they begin to become acquainted with the personalities of their peers. Throughout their deliberation, not a single juror calls another by his name because the names are unknown by the jurors.