Director Joe Wright is fascinated with Saoirse Ronan’s blue eyes, entirely understandable. Her cerulean gaze is so pure, so clear, so direct, and at the same time knowing and innocent that it is perfect for the role of Hanna, a 16-year-old girl who has been trained as an assassin by her father, Erik (Eric Bana) and lived since she was a baby. They live in a frozen and remote corner of Finland, eating the wild deer and wearing skins to stay warm.

When Erik gives Hanna the choice to leave, here is what she knows: several languages and more than several ways to kill people, to be on guard even when she is asleep, that people will try to capture or kill her, and a fake backstory complete with the names of her school, best friends, and dog. Here is what she does not know: tea kettles and ceiling fans, music, other teenagers, families, small talk, and whether there is anyone she can trust.

She also knows that she is ready to leave Finland and ready to stop pretending to defend herself and do it for real. So Erik puts on a suit and walks off into the snow, leaving Hanna to be captured and fight her way back to meet up with him. Wright, known for classy literary adaptations “Pride and Prejudice” and “Atonement” makes this a thinking person’s action film with stylish fight scenes and a “Bourne”-like existential core. Hanna’s age and inexperience make her vulnerable despite her training. And like all teenagers, she is thrilled and a bit terrified by her discovery that her father did not tell her everything and does not know everything.

Only someone who has spent the past 15 years in a remote, snowed-in corner of Finland will not figure out where this is all going, but there is much to enjoy along the way. There’s a Luc Besson-ish detour as Hanna meets up with a traveling English family and is as flummoxed by their bickering and cultural references as she is beguiled by the song they sing together as they drive. We get our first look at Hanna’s nemesis, CIA hotshot Marissa (Cate Blanchett) in her apartment, all in shades of pewter except for her red hair, brushing her teeth with a ferocity that shows us her steely resolve, as slender and focused as a whippet. Marissa brings in a kinky free-lance agent played by Tom Hollander (Mr. Collins in Wright’s “Pride and Prejudice”).

Wright sets actions scenes on a loading dock and in a fairytale amusement park. A Hansel and Gretel candy house is a literally upside-down version of the snow-covered cabin she shared with her father. The references to Grimm work as well as the gritty chases and hand-to-hand combat. It’s a stylish thriller with a lot to watch and a lot to ponder.

Parents should know that this is an action thriller about a teenage girl who is a trained killer. There is a great deal of peril and violence, some graphic, brief strong language, drinking, and a few sexual references including a description of an hermaphrodite.

Family discussion: How is “Hanna” similar to the Bourne movies and how is it different? What did Eric leave out that he should have taught Hanna? Why did Eric leave his job? What do we learn from Marisa’s choice of clothes and the scenes of her brushing her teeth?

If you like this, try: The Bourne series and “The Professional” with Natalie Portman as a young girl taken in by a hitman.