A lesson in uncivic selfishness and the value of city ordinances. A public health officer describes an event at a coastal city where a wharf owner bribed a health inspector to ignore an infestation of rats. An outbreak of plague hits - first a dockworker dies then others near the harbor. The police join the health department in searching for the bribed inspector, who's holed up in the mountain cabin of the dock owner. As more die, it becomes urgent to find the inspector and his notes. The doc and the cop set out to catch a man's conscience.