For as long as she can remember, 15-year-old Hanna (Ronan) has lived with her father (Bana) in a world of total isolation.  They reside in a tiny wooden shack hidden away in a snow-covered forest just below the Arctic Circle.  She’s never interacted with another human being and she’s never even heard music.  Her limited knowledge of the outside world has come exclusively from her father and a small number of books.

The film’s opening scene shows us that Hanna is no ordinary girl.  She stalks an unsuspecting deer and then kills it using a simple bow and arrow.  It’s all part of her father’s plan to transform her into the ultimate assassin.  Hanna is put through a gruelling training regime each day in freezing cold conditions and has developed into a ruthless young girl who is incredibly fast on her feet.

It’s a curious introduction that takes an equally curious twist.  Hanna is given a transmitter by her father and she flicks the activation switch.  The time has come.  Her father packs his things and walks out the front door.  He tells her that they’ll rendezvous at an abandoned amusement park in Berlin.  Between now and then, she’s on her own and must complete her mission.

The transmitter instantly grabs the attention of CIA Agent Marissa Wiegler (Blanchett).  She’s been waiting for this day for a long time.  She tells her superiors that the situation must be contained and a fully-armed team is immediately dispatched to the transmitter’s location.  On arrival, they find the young Hanna and take her into custody.  She doesn’t even put up a fight.

I won’t divulge too much more at this stage.  Hanna is an intriguing action-thriller that’s best described as a cross between Run Lola Run and The Bourne Identity.  You won’t be 100% sure about what was going on but that’s why it will so easily hold your attention.  Who are the good guys?  Who are the bad guys?  It’s not as simple as black and white.

Saoirse Ronan (Atonement, The Lovely Bones) is one of the finest young actors working today and she impresses once again with this challenging role.  Hanna is finally getting a chance to see the world but she’s finding it hard to reconcile.  She meets some very friendly people (such a nice family who she travels with) but also some very nasty people (such as those out to hurt her).  This contrast is humorously illustrated in a scene where she meets an attractive boy for the first time.

The film is certainly a departure from director Joe Wright who is better known for his period romances Pride & Prejudice and Atonement.  He has quickly adapted himself to the action genre and made a wise move in selecting The Chemical Brothers to put together a funky film score.  I don’t know how long it took to shoot some of the scenes but Saoirse Ronan must have been exhausted by the end of it.  She does so much running!

The film’s weakness is its finale.  When you see all the pieces of the puzzle fitted together, the result is underwhelming.  My first comment to a friend on leaving the theatre was that I liked the film’s style but it “needed more plot”.  I also have question marks about the relevance of an incompetent attack team employed by Agent Wiegler (led by Tom Hollander) to track down Hanna.  Too goofy for my liking.

Yes, this could have been better but Hanna should be seen for its attempt to bring style back to this well trodden genre.