Hanna is an odd combination of action movie and art film, seamlessly bouncing between calm pastoral moments and Bourne-style fight scenes. Saoirse Ronan plays the titular heroine, a teenage assassin sent to kill the woman responsible for the death of her mother. Eric Bana plays the man that raised her and trained her to be a perfect killing machine in the desolation of the harsh Scandinavian wilderness, without any of the amenities that we in modern society are accustomed to. Most of the movie takes place as Hanna wends her way through the world, confused and unable to completely comprehend minor social interactions and things as simple as light switches. In the moments between Hanna killing her persuers, we see the wide-eyed innocence of a young girl in an alien world.
It's a beautiful-looking film with interesting techniques, often accompanied by a strange but somehow fitting electronic soundtrack. The acting is excellent; Ronan plays the role of Hanna better than most adults could. Rarely have I see any child actor play anything as well as this. Bana and Cate Blanchett give some star power to the cast and Jason Flemyng and Olivia Williams round it out with minor roles. I can't think of any problems with the choice of cast or crew working on this film.
The one failing of the movie that takes it down the notch from "great" to "good" is its somewhat-sloppy and less-than-satisfying writing. It would be hard to complain specifically without spoiling the movie, but let it be said that I could write an essay of what the script does wrong in its final third. The intelligent, inquisitive and ruthless Hanna makes several strange decisions and suddenly turns into a nervous, self-aware and petulant teenager, despite the fact that this defies all logic. She allows people she's been shown to love to be hurt, runs when she could easily kill her attackers, and shows none of the tactical intellect and quick thinking that she showed in an extended setpiece toward the story's beginning. The complete change in tone and outright stupid choices in writing soured the entire end of the film. What could have been a truly great picture was diminished by the sloppiness of the plot.
Still, as sloppy as it is, it's hard not to recommend the film, as it's an experience that I don't think I've seen in film, combining the visceral with the innocent. It's both an excellent action piece and a strange coming-of-age story all tied up with the verve of an art house film.