Maybe this is why I thought 21Grams was such a terrible movie. Your character can still surprise you even if you've mapped things out. But if you're just going along writing blah, blah, blah, it's gonna play out that way. 21 Grams is one of the worst films I've ever seen.

I had a bit plot problem with that movie. After the wife, played by Naomi Watts, loses her husband and children, she is supposedly so discombobulated by the deaths, she refuses to press charges against the driver who killed them, played by Benicio del Toro. It felt completely out of character from someone who has suffered that type of loss and smacked of 'writer's convenience' - because if del Toro's character had been tried and imprisoned, there would have been no movie; that is, Arriaga forced the character to make a really stupid decision - not go after del Toro's character through the legal system - so that Arriaga could tell the story he wanted to tell. So basically at that point in the story, I checked out because I didn't buy Watts' character's actions.

It's been forever since I've seen the movie, but didn't Naomi end up not wanting to kill Benicio del Toro, and tries to stop Penn's character at the very end? So I think that's pretty congruous with her character arc, if she decides against revenge at the last minute, and then just lets bygones be bygones (essentially). I mean, Penn's character was all alone in the hospital in the final scene, so it's obvious it wasn't a total one-eighty for her just in regards to not charging del Toro.