The startling opening scene of La Rupture recalls the first few minutes of Hitchcock's Young and Innocent, with both films beginning with sequences of frightening marital strife that apparently conclude in violence. There's no time to settle in to either film, and it's a jarring strategy that ensures we're off balance for the remainder of either film. That La Rupture begins with what seems like an homage to another film is appropriate, too, for Chabrol weaves similar quotations into the remainder of the film - most obviously with the inclusion of a tram scene that references Murnau's Sunrise.
The Hitchcock comparison seems especially apt, given that both films are a blend of themes and tones: Young and Innocent is by turns lightly humorous, tense, and brutal where La Rupture veers from the mundane to the outlandish and drug-addled (with a bizarre film-within-a-film just to top things off). Chabrol's protagonist, played by Stéphane Audran, is a generally credible working mother who finds herself in a strange boarding house filled with comic types (the card-playing old women, the ham actor, the drunken buffoon landlord), and there's a constant sense of being off-balance for we never know quite how a scene will play out: the climactic act of violence comes complete with pop-up comic effects, whereas the matter of a child custody case has more conventional legal discussions and parental jockeying.
Chabrol extends that sense of the unexpected with his filming style, and particularly his editing choices: one shot cuts abruptly to the next, making us wonder how much time has passed or where we are. It's very difficult to make out the geography of the boarding house as a consequence, although the quick cuts do add a great sense of urgency to the film, and particularly help to foster tension when we're never quite sure when a character might reappear to upend carefully laid plans.
(The picture above was taken from Ed Howard's blog; I watched the film on VHS and was unable to get any decent frame grabs).