Let us be very clear from the beginning, the person who came up with Murderous Maids could not have seen or understood the film. The Injured Assassins, or Injured Killers (assassins just sounds better to me) is much more evocative of the feel and content of the story. For this is not the story of a murder, but the story of two sisters who happen into murder.
First, Sylvie Testud is superb, restrained yet full of emotion, humble but full of pride, cold but full of love.
Many people have commented on the class warfare. The Jean Genet play takes that to an extreme. Some have been pulled in by the story of incest and illicit love between sisters. Denis walks deftly across these problems and presents a story that unfolds itself authentically and truly.
The mother in this movie did give me problems, she seems nicer than her effect on the girls, but remember who it is that puts them in the convent, and how she hides the secret of the oldest sister's pain using it only as a weapon to inflict damage upon Christine (Testud).
As the film came to the climax I briefly thought of Chabrol's Le Ceremonie, but that is another story, another film. Though depressing and slow, but not a second too long, this is a seriously important film for those who value the intensity with which cinema can bring the truth to light.