The marchioness of Botarin secretly exchanges passionate letters with Jean, a young sailor. What Jean doesn't know is that the lady of his heart is twice as old as he thinks, for the photo she has sent her was one of her young niece Jacqueline, instead of her. Things get complicated when Jean turns up at the Botarin manor, escorted by two other sailors. The young man immediately falls under the spell of Jacqueline, which drives the marchioness crazy. The latter resorts to various subterfuges to separate the lovebirds, but to no avail. She will end up marrying a gendarme who has been her suitor for years while Jean weds his beloved Jacqueline.

The Baroness de Courtebise presides over an association of mothers-in-law with grievances against their sons-in-law. Armed with her prerogatives, she forbids the marriage of her daughter-in-law to the mayor's nephew, especially as an inheritance is in doubt. The ladies kidnap, the men kidnap, the election campaign turns sour and the Baroness must capitulate. She takes revenge by falling into the mayor's arms.