A young inventor is kidnapped to force him to tell the secret of his invention, but he foils his captors thanks to a pen with invisible ink.

Chichinette (Blanche Montel) is in love with a playboy named Philippe (Jean Devalde). She follows him to Paris, believing his promise of marriage, only to come to her senses.

Two war orphans, Joseph, apprentice printer, and Lisette, typist, live with their grandmother in Belleville. Lisette loves his next door neighbor, the painter Amedee, but this one does not offer him a union. Joseph Amedee learning is the son of a general, advocates for Lisette and everything ends in marriage.

René Dargelle is asked by a friend to receive a young woman in his place. She is soon to marry a Hindu prince, a man who is certainly attractive, but who cheats on her shamelessly and whom she dreams of making jealous. When Dargelle, out of pure fantasy, asks her to tell right and left that he seduced her, she sees the perfect opportunity to infuriate her noble lover.

When an unscrupulous banker ruins his family, a young man swears to bring him to justice, so he adopts a new identity, the mysterious Judex, and ominously disguised and sunk into the muddy path of vengeance, punishes the crooks and protects the innocents. (Originally a twelve-part epic serial.)