“Insidious Weapons” are those long and pointed shining pieces of steel which “Madam” uses to hold on her latest “Chantecler” hat. Madam starts upon a shopping tour, but is unfortunate enough to board a car filled with men. One of her hatpins, the “Insidious Weapon,” protrudes from her beautiful bonnet and at every lurch of the car some poor fellow receives the point of the weapon in the eye. At last the men, aroused in indignation and anger, cause Madam’s arrest. When taken to court, the judge, learning of Madam’s extreme carelessness, sentences her to a long term in prison.