The scenes set in Pierre Lachenay's apartment were filmed in Truffaut's own home.
The man who hassles Nelly Benedetti in the street is the co-writer of the film, Jean-Louis Richard. When they were filming, passers-by came to Benedetti's assistance and had to be fended off.
The film's seemingly melodramatic concluding incident is actually based on a real event which François Truffaut read about in a newspaper.
This film was booed by the audience at the Cannes Film Festival in 1964 and did poorly at the box office.
The airline featured in this picture, Panair do Brasil, ceased operations the next year on February 10, 1965, by order of the Brazilian government under controversial circumstances.