Hanna Heller, portrayed by Saoirse Ronan, is a 15-year-old girl living in the remote wilderness of northern Finland with her father, Erik Heller, played by Eric Bana. The story begins with Hanna demonstrating her skills as she hunts a reindeer, showcasing her lethal proficiency. Trained since she was just two years old by Erik, an ex-CIA operative, she has been molded into a highly skilled assassin. Erik, having left the agency, goes into hiding in the Arctic to shield Hanna from the dangerous world outside.
Their lives are complicated by Marissa Wiegler, a senior CIA officer, portrayed by Cate Blanchett, who seeks to eliminate Erik due to a secret he possesses. Erik intends for Hanna to confront Marissa, having prepared her for this moment for years. While living a life devoid of modern influence, Hanna immerses herself in a desolate world of Bloody fairytales, where her knowledge and survival skills are unmatched. When Hanna declares she is ready to face their adversaries, her father hesitantly provides her with a means to alert the outside world.
After a decisive attack on two special forces operatives intruding upon their cabin, Hanna is taken to a secret CIA compound. There, Marissa grows wary of Hanna's intentions, sending in a body double to test her. A heartbreaking charade unfolds when Hanna confronts the double, leading to a violent escape from her captors. Now free, Hanna's chase takes her across the Moroccan desert. Here, she unexpectedly crosses paths with a British family—a couple, Sebastian and Rachel, along with their teenage daughter, Sophie, and young son, Miles—who unwittingly become her allies. During her time with them, she forms a bond with Sophie, blossoming into a brief, innocent romance.
As they journey through Europe towards Germany, the shadow of danger lurks, with Marissa hiring the ruthless Isaacs to capture Hanna. Their paths inevitably converge in France, where a violent showdown ensues, but Hanna manages to evade capture. Hanna's quest leads her to her father's old acquaintance, Knepfler, whose whimsical abode within an abandoned amusement park proves pivotal. Amidst tales of deceit and the chilling truth that Erik may not be her biological father, deep bonds of betrayal surface.
The film escalates as Marissa and Isaacs close in on Hanna, prompting Erik to make the ultimate sacrifice as he seeks to protect her. A heart-pounding climax unfolds as Hanna and Marissa confront each other; the confrontation laden with tension as Hanna pleads for peace, only to find herself in a life-and-death struggle. In a thrilling culmination, Hanna pursues Marissa through a water park, culminating in a fierce fight for survival. With the stakes higher than ever, Hanna's resilience shines as she takes aim, mirroring the very opening scene of her hunt, this time exacting her vengeance in formidable fashion.
