This is one of those movies that is frustrating because you want to *talk* to people about it, but you really can't until they've seen it.
It stars Uma Thurman and is directed by Vadim Perelman, whose previous film was the excellent House Of Sand And Fog. It also stars Evan Rachel Wood, who was so good in King Of California. They had me at Uma Thurman. :-) She plays a woman who is married to a handsome college professor and has a beautiful young daughter. But as the 15th anniversary of a Columbine-like school shooting that she was present at approaches, memories of that day and the days leading up to it start to encroach on her perfect life, and it starts to unravel, as does her grasp on reality. The story is told by jumping back and forth between her life in the present and memories of her in high school. It's masterful storytelling IMO, and beautiful visually as well. It's also much more than what I describe above, but if you choose to see it you'll thank me for not saying more.
