Dany Longo is red-haired, beautiful, disturbed, passionate–and nearsighted. As she speeds through the south of France in a purloined Thunderbird on an errand for her employer and his wife, no one, including Dany herself, knows where she is headed–or why she is going there.

The third in a series of films featuring François Truffaut’s alter-ego, Antoine Doinel, the story resumes with Antoine being discharged from military service. His sweetheart Christine’s father lands Antoine a job as a security guard, which he promptly loses. Stumbling into a position assisting a private detective, Antoine falls for his employers’ seductive wife, Fabienne, and finds that he must choose between the older woman and Christine.