Happenstance is a 2000 French comedy film starring Audrey Tautou and Faudel. Le Battement d'ailes du papillon is its original French title and is sometimes known by the literal translation, The Beating of the Butterfly's Wings. The title references the Butterfly effect from chaos theory which is quoted at greater length by one of the characters in the film.
[The following section was flagged as an advertisement in Dec 2007 but is in fact identical to the plot summary in http://www.imdb.com/title/tt0243135/plotsummary. "Chance, volition, and the large effects of tiny causes swirl through Paris on a single day. Before the day ends under a full moon, twenty lives intersect time and again in unpredictable, connected ways: a jilted lover holds a souvenir pebble, a stolen coffee maker looks suspicious at a Metro stop, a yellow rain slicker is passed on as a gift, lettuce causes a bicycle accident, a leaf betrays a habitual liar who's just told the truth, and an Algerian waiter, also born 11 March 1977, sees a bug cross a tablecloth. Magical sand from the Sahara is in the air.]"
plays a shop assistant on the way to work who takes a seat on the Paris metro opposite an older woman who tries to interview Tatou for a marketing survey. On hearing Tatou's birthdate is 11 March 1977, the woman reads her horoscope : today she'll meet her true love, but she must be patient. After Tatou leaves the metro, a young man sitting alongside (Faudel
) tells the older woman he was born on the same day and asks her to read the rest of the horoscope.
The film then traces a range of characters of diverse ages, ethnicities and social status whose daily lives intersect with Tatou and Faudels in a variety of gratuitous ways and come together in an implausible ending at the end of the day.
An Franco-African woman nightwatchman shoos a sleeping tramp from a building. He later becomes the centre of events at a metro where other characters come together and later in the movie recount the event from diverse perspectives. A young man seeks a job at a museum - delayed by the incident at the metro - arrives for the interview late, is hired by a young woman who agrees to meet him across the road for a coffee. He waits in the cafe where two other characters are sitting independently. One is a man trying to find the courage to break up with his wife and/or his mistress - unable to decide, he uses the outcome of the actions of the man at the next table to determine what to do. The woman at the museum writes the new employee's name on a piece of paper, cuts them into the separate letters, shuffles them around until she finds that the form the anagram of a pederast and ... so it goes. The throwing of stones, a shoe and other trivial events determine the decisions and lives of the many characters.
The film relies heavily on the notion of chance and happenstance interacting in unpredictable ways on people's lives. It is a film whose action/plot appears heavily driven by the underlying chaos theory that gives the French film its title. This may be seen as giving the film an unnatural naturalism where the auteur's hand rest heavily on the lightness of the chaotic mechanisms.