At a gathering of would-be society debauchees, the Baron Plessis de Regard and the attractive young Nathalie hatch their individual plans to use sex to respectively ruin and punish their selected enemies. The Baron's plan is to scupper the political ambitions of right-wing parliamentary candidate Colonel Montvilliers by setting him up with a female companion and publicly exposing his new-found vices. Nathalie's quest is of a more personal nature, to destroy her estranged father Charles Leroy-Merville by corrupting his innocent 17-year-old daughter Sophie, a task she intends to achieve by securing employ as the girl's summer tutor.
