- Breakthrough Hit: Éric Rohmer's first hit in France.
- Cast the Expert: Daniel Pommereulle was a prolific painter and sculptor in Real Life (He Also Did acting, filmmaking and poetry writing).
- The Danza: Haydée (Politoff) and Daniel (Pommereulle).
- He Also Did: Sam is credited as having been played by "Seymour Hertzberg", but that's actually a pseudonym for New York Times film critic Eugene Archer, who'd spent some time in France and worked with Rohmer at Cahiers du Cinéma.
- Real-Life Relative: Mijanou Bardot (Carole) is married to Patrick Bauchau (Adrien).
- Unintentional Period Piece: Haydée is very much into the androgynous fashion style (short hair, male-type clothes) that was big at that point of The '60s, popularized by Twiggy.
- Writing by the Seat of Your Pants: Quickly put into production when My Night at Maud's got delayed (hence the Out of Order "#4" numbering), without a finished script. Patrick Bauchau, Haydée Politoff and Daniel Pommereulle improvised and developed the characters so much that they all shared writing credit with Rohmer.
Trivia / La Collectionneuse