Chang-hi-tang, a beautiful sixteen-year-old girl who has been sold to a house of ill repute to keep her family from starving. Immediately befriended by a wealthy man, the delicate and talented young girl is brought as second wife into a childless household. Her sweet demeanor and her ability to bring forth a son cause the first wife to vow revenge. Hi-tang, above reproach, follows her mentor’s directions in all things, even to serving the tea with which the elder wife poisons her husband. Hi-tang is accused of the murder by the elder wife, who also claims that Hi-tang’s son is really her own. the wise emperor devises a test. He orders the child placed in a chalk circle, from which each wife may try to pull the child and claim him. Because of her true mother love, Hi-tang refuses to try pulling her son away from the other woman across a chalk circle, for fear of hurting him. She thus proves her innocence. She is made empress when it is revealed that the new emperor is the true father of her child. Hi-tang had always thought that the prince had come to her only in a dream.
Ma Chun-shing, the duped husband whose first wife is unfaithful and treacherous while his second is always loving and trustworthy. He elevates in his heart the beautiful young wife and thereby brings down the wrath of the barren Mrs. Ma. On one occasion, the victim of jealousy, he believes his young wife has given away jewels and robes to a lover, but he discovers that the man is her unfortunate brother. When Mr. Ma considers divorcing his first wife so that he may elevate Hi-tang to the position of first wife, Mrs. Ma poisons him.
Mrs. Ma, the vindictive first wife of Ma Chun-shing, who claims Hi-tang’s son as her own and contrives with a lover to poison her generous husband. She is unable to find fault or complain against the model second wife for many years, but a plot of revenge finally reaches fruition. With bribery and mendacity, the evil woman wins the trial, has Hi-tang imprisoned, and thus keeps the young son and the fortune of the family. When she is called to a high tribunal by the new emperor, her evil deeds are revealed and her fate is sealed.
Chang-ling, Hi-tang’s brother, a young scholar embittered by the duplicity and oppression of the government’s representatives. Arrested for expressing doubts that the new emperor will improve the lot of the common people, he is taken before the same high tribunal as his sister. the new emperor is in sympathy with his ideas of reform, however, and Chang-ling is not only pardoned but also made a judge in place of the evil Chu-chu.
Chow, a clerk in the local court, the lover and accomplice of Mrs. Ma. This despicable man cruelly watches virtue suffer and vice triumph as he carries on him the poison his mistress finally asks of him. Calculating and brutal, he conspires to rig the trial and bribe witnesses until he at last is brought to justice.
Chu-chu, a judge of the local court who accepts a bribe to find Mrs. Ma innocent and Hi-tang guilty. He sentences Hi-tang to death, but before the sentence is carried out, all involved are called before the new emperor for an investigation. Chu-chu’s decision is then overruled, and he loses his judgeship to Chang-ling.
Prince Po, one of the old emperor’s sons and later the new emperor. As a dashing young prince, he had fallen in love with Hi-tang, and on her wedding night he had stolen through her window and made love to her as she slept. Thus, her child is actually his, not Mr. Ma’s. When Hi-tang is brought before him, he recognizes her, and after learning the truth in the case he metes out justice to the evildoers and makes Hi-tang empress.