Hanna is the kind of movie that even though it is highly derivitive, it is still highly enjoyable. Hanna is played by Saoirse Ronan, previously seen in The Lovely Bones. To put it mildly, that was not a great movie, but she was great in it, which can often be the mark of a truly great actor or actress. She's excellent as Hanna, a teenage girl who has lived her entire life in seclusion with a former CIA operative (played by Eric Bana). Hanna eventually enters the real world and Ronan does a fantastic job portraying a girl who is alternately curious about everything around her and can turn into a deadly weapon at any moment. Being that title of the movie is the name of the protagonist, everything rests on Ronan's shoulders in terms of this movie being good and she does so effortlessly.
Playing Hanna's father/the CIA agent that trained her is Bana, who is also excellent. That's nothing new for Bana either as he is another actor that can bring a movie to another level. Erik Heller is his name and he raises Hanna far removed from society (the reason for which you eventually find out) and for good reason. Heller does what he can to protect her but like all children, curiousity eventually gets the better of Hanna and she decides to go off into the world. Bana is convincing as the father who only wants what's best for Hanna. Chasing Hanna is Marissa Weigler, played by Cate Blanchett. This will sound a bit repetitive, but Blanchett is another actress who cannot be bad in a film. That's "bad" as in being an untalented actor, not a villainous type which is exactly what she is in Hanna. Part of what makes her performance great in this movie is that it's clear she had a lot of fun being a borderline maniacal high level CIA operative. She's manipulative, souless, cunning and Blanchett is pitch perfect in portraying those qualities. She also deserves a lot of credit for making this movie better than it deserved to be.
And I say that because this is a highly derivitive film. Hanna feels like The Bourne Identity mixed with Run Lola Run and typically that makes a movie less enjoyable when it wears too much of its influences on its sleeve. But with all the great acting, the sharp cinematography, the well executed direction of Joe Wright and the tight editing of Paul Tothill, Hanna is a fun watch. Also making this film fun is the soundtrack composed by The Chemical Brothers which gives Hanna an intensity and coolness that a traditional score likely could not have achieved. Be sure to hit up the Cinemagics in Merrimack or Hookett to see Hanna.