A little girl named Hanna who is in the snowy forest watching the movements of a wild deer. Hanna approaches the deer until she has the opportunity and hits it with an arrow. The deer is hit by the arrow and runs away quickly while it bleeding. Hanna chases after the deer until the deer falls to the ground. Hanna takes out a gun and kills the deer. Then her father Erik appears behind her and tells her to be more careful later on. At that time, Hanna tries to hit Erik, but she loses the fight and learns her lesson, and drags the deer to their house so that they can eat it. As their house is in the forest, and Erik notices that his daughter Hanna is upset because of what happened, and he tells her that she must always be careful and not lower her defenses, and Erik tests her in more than one language, Hanna learns them, and asks her about general information, as Hanna is sixteen years old, and she never leaves the forest or deals with anyone from the outside world, and Erik takes a book about animals and talks to his daughter about the blue wheals.
Then, his daughter asks him what is mean by music, and Erik tries to explain to her the musical instruments and how melodies and songs harmonize with each other. But Hanna wants to hear music by her ears and tell him that she is ready to go out of the woods and see the outside world. So her father shows her a book that he used to hide from her, then Hanna she reads the book, flipping through its pages, seeing stories and pictures, and then falls asleep. One day, Erik and his daughter wake up, and they practice with each other the methods of fighting, and Hana exercises the way she speaks and the languages she learns, how to shoot, and she exercises physical fitness throughout the day. And at night she sleeps, then her father sneaks behind her while she is asleep and points his gun at her, as a test for her. Hanna succeeds in the test, as she managed to knock her father to the ground, tie him up, and tell him that she is ready to go to the outside world. Erik gets out of the house and digs in the ground and brings out something buried.
The next day, Hanna plays with a wolf and enjoys her time with him until she hears a loud sound of planes flying over her and Hanna screams of joy because it is the first time she has seen something like this. Hanna runs and goes to her father to tell him about what She saw, then her father told her to press the red button in front of her if she was ready to leave the forest. But Hanna back down from her decision to leave the forest and choose to stay with her father at home. Then the two go out together from the house and walk in the middle of the snow and watch the sunset after that Erik talks to her about the first experience of launching an animal in a spaceship into space, and Hanna closes her eyes and falls asleep. On the next day, Erik puts on his hunting clothes and hunting equipment, and before leaving the house, he asks Hanna if she wants to go hunting with him, but Hanna refuses to go with him and lets him leave alone. Then Hanna goes to the red button and press it, when she did that an alarm was turning on in a second house of a red-haired woman waking up and turning off the alarm, then she gets out of bed and brushes her teeth to start her day.
Meanwhile, Erik returns from his hunting trip in the woods and knows that his daughter pressed the red button, so Erik sat and kept thinking about their next steps. At the same time, a man came to the intelligence agency building and told Marissa, the red-haired woman, that they had discovered a signal in the snowy forest area and now they are able to know where Erik is. Then they held a meeting immediately, the agents discussing about killing Erik, and there was someone who wanted to make Interpol the ones to take over the mission, but Merissa convinces them that she can handle this mission, and she would be able to deal with the situation, meanwhile Agent Lewis enable to know Hanna’s location via satellite. Erik wears a suit and made himself look like a businessman, shaves his hair and beard, and leaves the house, leaving Hanna behind at home.
At night, the soldiers surround the house and two of them break into the place. When they are late, the rest of the soldiers enter to find that Hanna killed the two by her own. So the soldiers call Merissa and tell her they couldn’t catch Erik. Marissa demands Lewis to arrest Hanna and bring her to the agency. At the agency, they put Hanna in a room and an agent interrogates her. And the agent tries to be friendly with her and asks her what she wants, Hanna tells him that she wants to talk to Marissa, who sees and hears them. Marissa tells the agent that she will arrive at the agency at night so the interrogation is postponed, and the institution’s scientists examine Hanna’s blood sample and her DNA, and they were shocked by what they found. And the head of the laboratory tells the scientists to re-examine to be sure. Then Marissa arrives at the institution at night and brings a woman who looks exactly like her to enter the room with Hanna and the false Marissa wearing a speaker so Marissa tells her what she has to say and asks Hanna how and where she knew her father. So the false Marissa tells her a fabricated story about that she met Erik on a rainy day in Prague, then Hanna jumps from her place and hugs the false Marissa in order to attract the agents’ attention.
But they felt anxious and ordered the soldiers to return Hanna to the cell. So two soldiers went to the interrogation room and opened the door trying to inject Hanna with anesthetic. But Hanna was aware to that and kills the false Marissa and all the soldiers in the room. Then Hanna left the room and moved towards the way out of the institution. The soldiers tried to prevent Hanna more than once while she was looking for the way out. So Hanna enters the ventilation channels in the institution and crawls inside them until she reaches the storage room, then someone comes out of the bathroom to see Hanna with a gun in front of him and put it at him and Hanna enforces him to lock himself in the cupboard so she keeps running from the institution. And Hanna sees another scientist and pushes him away from her way, and the scientist sees her running away from the institution, with serval of soldiers chasing behind her. Hanna enters to the ventilation channels again, but this time she goes up towards the hole and pushes the cover to get out of it to find a desert and realize that the institution is located in an isolated place underground. When she pulled her head out of the hole, many army cars passed over her, and she was able to cling to one of them, and the cars moved with her while she was under them.
When she reached a place she felt safe she left the car and all she can see is desert. Meanwhile, in the institution, Marissa opens a safe and prepares a file unknown secret and burns it at night, which makes her remember the time when she was in charge of killing an entire family one day, which was Erik’s family, his wife, and his daughter Hanna, when Hanna’s mother was about to die and Erik ran away towards the forest with little Hanna. When Hanna walks in the desert, she meets a girl named Sophie with binoculars, and she examines the place, and Hanna introduces herself to Sophie, speaking with an unusual manner, and Sophie ignores her and her little brother Miles, then their family calls on them to return to car, and Sophie sees Hanna behind her, and asks her if she needs a ride to a certain place, but Hanna tell her that she will be fine and will walk on her feet in the desert. Meanwhile, Merissa is on a private plane belonging to the institution and tells her assistants to arrest Eric, not Hanna.
Then Hanna sees a group of women washing their clothes in the water of the river. So Hanna she stole some from their clothes and kept walking until she found a city and goes to a store that belonged to an old man and spoke to him in a language other than her own. Then the old man let her watch his television so that this would be the first time Hanna had seen television. So the man left Hanna in a room to sleep, but she is not used to the presence of electronic devices in the room, which frightened her, so she runs away and leaves to see Sophie and Miles. In another place, Marissa takes a taxi to reach a bar called Saffari, she enters and Marissa asks the owner of the bar for help, and he agrees to find out where Hanna is. Meanwhile, Hanna is in a hotel with Sophie and her family, having dinner together, and Sophie keep talking while Hanna is eating and watching them. And Sophia’s family asks Hanna where she came from, and when they know her real story, they were shocked and felt sorry for what happened to her mother. At night, Hanna hears the sound of the call to prayer (Adhan) in Muslim mosques, and she was able to translate the meaning of the call to prayer (Adhan), and then reads the report that she stole from the laboratory regarding her DNA sample.
On the second day, Sophie is fighting with her family in the car when they reach a crowded area, and they are not aware that Hanna are with them in the car after she climbed on top of it yesterday. In another place, the owner of the bar and his assistant tied a man to a chair, and they checked the security cameras to find what they wanted to know about Hanna then they killed the tied man and left the place. Meanwhile Hanna stays in Sophie’s family’s car and watches from her place where she is hiding to know if someone is chasing her and the owner of the bar gets out of his car with his assistant and they head to the market. At the same time, Erik comes out after swimming in the ocean but sees two officers in front of him. And there is an agent on the bridge waiting for Sophie’s family’s car to come, and when the car passed under the bridge, the agent rides a motorcycle and chases them, while Hanna watching the family from her hiding places and they were playing and singing together.
Then Marissa and Lewis go to the ocean beach after they bring out the bodies of the police officers who was killed by Erik in order to escape to the city, and Marissa warns Lewis not to tell the Interpol about this problem. At night, Hanna comes out of her hiding place and goes to a swimming pool and starts to drink its water with using her hands because she feels thirsty. Sophie comes out of the pool and tells her about the boys playing together in front of them. One of the children looks at Hanna and takes her behind him on his motorcycle. Hanna felt very happy and a feeling of freedom. The children arrived at a place and lit a fire in wood, camping out, playing music and singing. After the songs ended, Hanna sets next to the boy who owned the motorcycle, and they felt shy to each other. And when the boy tried to kiss her, Hanna hits him, knocks him on the ground, ties him up, then Sophie tells her to leave the boy. After that, Hanna tells the boy that she was happy to meet him then leaves. In the meantime, there are three agents who are checking the camps of the guests, and one of them, who is the owner of the bar, opens a camp and sees Miles, then he kept searching the other camps. Hanna and Sophie return to the camps, and Hanna notices that something strange is happening.
Meanwhile, Marissa goes alone at night to an old woman and wakes her up from sleep, the two keep talking to each other while they smile. Suddenly, Marissa takes out her gun, puts a silencer on it, and shoots the old woman. At the hotel, Sophie asks Hanna about her where she really came from, not what Hanna told her family, and Hanna says that unfortunately, she will not be able to disclose such dangerous information, and begs Sophie to understand, and Sophie did not understand anything, and why Hanna cannot tell her the truth. Hanna asks her if we can remain friends and Sophie agrees and gives Hanna a bracelet as a symbol of their friendship. On the second day, the family searches for Hanna and Sophie tells them that she went out last night, and suddenly Hanna appears and tells them that she brought a breakfast after killing an animal and brought it to them.
During this time, Erik gets out of the bus at the station and moves around the city and feels that someone is chasing him and keeps walking while being aware on his way to the subway and notices a strange man behind him, then Erik looks around him to see another agent and one of them tells the institution that they have arrested Erik by wireless, but Erik hits and kills them then takes the wireless and knows more information about Marissa. In the main time, Hanna is with Sophie’s mother in the car, talking to each other while they are moving, and Hanna notices that someone is chasing them. At the moment, Marissa stays at home, brushes her teeth, listens to an audio recording, then someone calls her, Marissa picks up the phone to find that Erik is the one who calling her. The two talk to each other for a short time, and Marissa tries to convince him to rejoin the institution, and suddenly one of her agents get shoot, so that Marissa realizes that Erik knew her address then she escapes from the window before he came to her. At night, the same car kept chasing Sophie’s family’s car, and the mother parking the car and leaves to check her map. Also, the car chasing them stopped and Hanna tells them to keep quiet in the car. Then, Hanna thanked Sophie for her kindness.
And she quickly ran away from the car and the agents chased her until they reached a place with huge containers packed together in a way like a maze. In the end, they managed to catch Hanna. But Sophie was worried about her friend and goes to check on her, then she sees Hanna killing one of the agents, and Sophie got scared of her and ran away quickly from the place. The Hanna hits them and managed to escape and jumped into the water, but the agents caught Sophie and her family and took them to Marissa. Then Marissa talks to them privately to find out where is Hanna.
Meanwhile, Hanna is on a boat heading to an unknown location. Merissa talks to little Miles, who tells her where Hanna is going. So Hanna arrives in a city and walks through the streets until she reaches a place that look like a forest and contains dinosaur statues. She arrives at a solitary house then a man sees her and welcomes her before giving her an envelope with Erik’s address. He brought her food and a passport, and told her that she needed a picture for her. The two talked about Hanna’s mother while they were listening to music. Then Marissa arrives at the man’s house and breaks into the place with her assistants. Hanna was able to hide under the bed and the agents searched the house. Marissa receives a call from her manager, shouting at her because she went alone without support. And Hanna managed to runs away and goes to the city to find a cafe, where she uses a computer to search for her father’s name. While Erik arrives at his friend’s house to see the agents there, and when he finds out about how the situation went, he runs away.
And Hanna break into a house where she finds Erik then asks him if he was her real father, so Erik told her the truth and that Hanna was the result of genetic tests to make super soldiers. And Erik tells her that he loved her no matter what, bur Hanna gets angry when she finds out about the truth and tries to leave the house, and Erik tried to stop her. When the agents arrive at the house, and the two run away in opposite directions, and the agents chase Erik in their car, and they get out of it to chase him and Erik keeps fighting with the agents, until Hanna can escape. But Marissa shouts him and kills him. While Hanna returns to the house of Erik’s friend to see that there is nothing left there, then she hears Marissa ‘s voice calling her, Hanna took an arrow and ran away from the house. Merissa chased after her in the forest until she caught her, Hanna told her to leave her alone and that she did not want to hurt anyone again. When Hanna left, Merissa tried to shoot her, but Hanna sensed danger and shot the arrow at Merissa and chases her while following the traces of her blood, but Merissa could not escape, and when she tries to put the gun to Hana, she falls from a high place then Hanna takes the gun from the ground and killed Merissa.