One of the ladies from my circle dancing group had seen it and recommended it, and since I'd been to Paris recently, I was still feeling in a French frame of mind, so decided to see it at the local cinema.
It was quite a low key film, although it dealt with a shocking subject. (I won't discuss the plot, since the slow reveal of the past history of the two sisters is one of the ingredients of the film.) KSK was very restrained in portraying the main character, which I felt worked well since you had to concentrate more in discerning her emotions. Also she was very isolated at the beginning of the film. That meant you became more involved in her story as she became more relaxed in her new situation, and made connections to others; and you had more empathy with her past actions as they're revealed.
There were many other characters, both family and friends, and observing all their interactions was like eavesdropping on a bus, with little snapshots of their lives. There was an admirable and realistic little girl, who had the second best line in the film: "I want to be a scout." (It works better in context.)
But the best line is the final one. After a powerful scene between KSK and her sister which resolves the tension between them, someone off screen calls out, "Where are you?" and KSK shouts, "I'm here", and then looks at her sister and repeats the line quietly to her, communicating that the journey she's been on since the beginning of the film is completed.