Overbearing but kind-hearted old industrialist Sir Henry Woodstock (known as "Old Iron" to his family) quarrels with his favourite son Harry because Harry wishes to marry the daughter of a business opponent whom he suspects of shady practices. Harry, who has inherited his father's temperament, drives away in a blind fury, runs a man down and kills him. At his trial for manslaughter Sir Henry's testimony as to the quarrel, and the mental disturbance that must have resulted from the conflict in Harry's mind between love of his father and determination to do what he himself thought right, secures Harry's acquittal.