 After the rejection of their latest - and preposterous - scenario, two script writers get back to basics to prepare a new movie. The new scenario centers on Henriette, a pretty, lively Parisian, and how she spends the 14th of July in Paris with her fiancé. We follow the tribulations of Henriette as various other characters make their entry in the story and turn a traditional festive day into something more adventurous than expected.