Director Agnès Varda later admitted the title 'Kung-Fu master!" was terribly misleading on a commercial viewpoint. Some foreign distributors even bought the film on the wrong impression it really dealt with the wild adventures of martial arts warrior.
Jane Birkin (Mary-Jane) is the real-life mother of both Charlotte Gainsbourg (Lucy) and Lou Doillon (Lou). Mathieu Demy (Julien) is the son of director Agnès Varda and Jacques Demy.
Léa Drucker, who went to the same high school as Charlotte Gainsbourg and was taking acting classes at the time, made her debut in the film, appearing as an uncredited extra in the role of a guest at Lucy's party. She went on to become a successful actress.