I just watched this last night, having been very intrigued by Audiard's other works, esp.the brilliant and somewhat indescribable Read My Lips. See How They Fall was indeed one of the more unusual stories I have seen in film. While the story has 4 main characters, it is the two most unassuming characters that anchor and propel the film. One is an over-the-hill depressive teddy bear of a salesman, Yanne. The other is a mentally slow/mentally challenged grown up child, Kassovitz. The former is searching for his only friend's killer; the latter is a puppy dog follower of a seedy petty criminal, Trintignant. (I've never seen Tr. in this kind of role. He is extremely convincing and completely revolting.) Most of the film builds the back story and follows the lives of the 2 pairs of friends. There are certainly elements of Midnight Cowboy and Of Mice and Men, but I was very pleased to see that the stories have many unexpected elements, mostly to do with Yanne, as he gradually leaves behind everything familiar to him and 'becomes' the quest to find his friend's killer. He moves obsequiously and with ease through worlds completely foreign to him, and the viewer's empathy is gradually drawn into the essence of who he is. One completely believes that he is who he is playing, and the same is true of Trintignant and Kassovitz.
The film's resolution occurs close to the end, when the 2 stories intersect. Before this, the film would have been greatly improved if 30% of it had been edited out, but the film's resolution is quick and perfect, like a gentle but effective 1-2 punch. In both Read My Lips and See How They Fall, Audiard shows a very unique way with unusual characters and their just-as-unusual stories. Both films are relatively quiet and contemplative, and the many silences lull the viewer into a distinct internal rhythm. Long after the films have ended, this rhythm stays on.