"The Devil's Dansant" is the nickname given to a dansant of which Dominique, a Frenchman, is the proprietor. District Attorney Farrar, while searching for evidence on which to raid the place, is astounded to find that his wife Valerie, is a frequent visitor at Dominique's. The willful woman disobeys her husband's orders and continues to visit Dominique's. Rogers, the Frenchman's silent partner, sees Farrar enter the place several days later. To avoid a scene, he helps Valerie escape by a secret door which leads to a gambling den above the dansant. Despite Roger's warnings, Dominique ensnares Valerie in his net, causing the woman to lose heavily at the gambling tables. The partners quarrel, with the result that Rogers gives Farrar a tip, causing the district attorney to raid the place. Farrar is thunderstruck to find Valerie among the prisoners bagged in the raid. By declaring she has been securing evidence for him the husband saves Valerie from disgrace. Dominique is convicted and ruined. Realizing, at last the extent of her folly, Valerie begs her husband for forgiveness.