The film tells the story of Hanna (Saoirse Ronan), a bright and curious girl who has been raised by her father, a former CIA agent, in the wild lands of northern Finland. Erik Hanna taught to hunt and learn a hard self-defense program. All education and training is reduced to a single goal, making it the perfect killer. But in the real world is a score to settle with the family of Hanna, and Erik realizes he can no longer retain more of her daughter.
This crucial moment of adolescence suddenly changes Hanna. It is separated from Erik and embarks on a mission for which it has always been intended. Before she and her father meet in Berlin, as we had planned, Hanna is captured by officers led by the ruthless intelligence agent, Marissa Wiegler (Cate Blanchett). Detained for observation under the Moroccan desert, Hanna reversed the situation with his captors.
His daring escape to the outside world throws an unknown landscape where you learn to understand and know how to guide. Marissa secretly sent a team of agents to the chase and she joins their search. As Hanna’s journey takes her across Europe and closer to their ultimate goal, is facing disconcerting revelations about his own existence and unexpected questions about his own human condition.