A girl is awakened on a rainy night and discovers that she has absolutely no memory of where or even who she is. However, a strange force leads her to a house where she is greeted by another girl called Leena who introduces herself as her sister and tells the girl that her name is Kara. After getting cleaned up, Kara is surprised to find herself hidden from her own mother when she calls for Leena. Leena evades her questions and Kara, in her dazed state, finds it easier to comply with her instructions and the next day, even agrees to be ridden to school on her sister's bicycle. At School, she is introduced with her sister's friends; Sheila and Mattie who are also in the know about her revival. Kara is then told to hide in an old bus and while her sister and her friends are discussing, Mattie lets it slip that Kara had been murdered. Leena scolds her friend and then along with Sheila goes to class, leaving Mattie in charge. Kara thinks she has found her chance to question Mattie, when Leena appears stating that her class had been cancelled. Kara is left frustrated and suddenly has a memory flash of herself all tied up in a small room. Before she could ask her sister, she spots a familiar boy coming towards the bus. Leena quickly turns the boy --whose name is Alex- away and Sheila enters their hiding bus stating that another student --Paige Marbelle, had been murdered and the police were all over the school. The friends decide to disguise Kara and try to pass her off as a sick student. Since the ID cards of the students were also being checked, it is decided that Kara would hold onto Mattie's Library card so as to avoid suspicion. Once inside the auditorium, Kara finds herself distracted when she notices a boy and girl who look familiar to her. Leena quickly tells her that they were her friends- Derek and Wanda. Kara has another memory flash in which she sees herself arguing with Wanda about something. After the announcement, Leena's classmate tells her that Paige had become good friends with Paige. Leena immediately assumes that they are the killers and complains to the police and the vice principal who turn her away because of the lack of evidence. When Sheila finds out about this, she tells Leena that it was her who had introduced Paige to Derek and Wanda. Leena then realizes that she had almost revealed her sister's identity and decides to take her home immediately. The friends are about to leave when, Alex offers to drive them home. Throughout the ride, Leena appears to be nervous about something else and once they reach home, tells her friends to take Kara upstairs. When she's finally alone with Mattie, Kara finds out that she had been really mean to her some years back and Mattie then tells her that she couldn't imagine why Leena had brought her back after what Kara had done to her. Kara is mystified and looks for clues in the closet where she finds a stack of pictures. It is then that she finds that Alex had been her boyfriend and when she looks out the window, she sees Leena and Alex hugging each other. Kara wakens in the middle of the night and finds Leena crying. Her heart goes out to her and Kara tries to console her. Leena then tells her sister how the family had fallen apart after she had died and Kara wonders if Leena thought that bringing her back would somehow fix everything. When she asks Leena if she had to give up something for performing the ritual that had brought her back, Leena again acts mysterious and Kara is forced to leave her alone. The next day, Kara puts her foot down and demands to be given a new identity so that she could live like a normal person instead of a fugitive. Leena tries to make excuses but gives in and days later, Kara is given a new identity of a girl called --Lily Lees. After her admission into school, she wastes no time in interrogating Alex after another memory flash had revealed that Alex had been there on the night of her death. But Kara is distracted by another flash where she sees herself putting back a book in the library while chatting with her friends. She also sees her mean side as she humiliates her sister in front of them. Kara is left confused and when Alex comes to her, she finds that he has been keeping an eye on Leena. After school, as the sisters are walking home, Leena scolds Kara for taking all the classes that clashed with hers, making it impossible for keeping an eye on her. Kara smirks but says she can't wait to meet her mother. However, when the reach home, Leena finds a letter that says that her mother had gone to see their Aunt Rose. Kara is disappointed and angry when she later finds that Leena had gotten her hopes up for nothing as she had been informed about her mother's trip beforehand. Kara decides that she has taken enough of her sister's attitude and the next day; escapes from school to go look for the woman who had helped Leena perform the ritual. The woman named Armine appears when Kara is in the cemetery who then tells her that her sister had made a deal with death and there was no way out. Her sister had exchanged her life for Kara's. Kara runs to the school and finds the police there once again. Sheila and Mattie inform her that Leena had disappeared while looking for her and Kara can't help but feel overwhelming guilt at how she had been mean to her sister. She goes home to look for more clues and finds her mother and father (back from rehab), rushing into a car. Kara decides to tell them about her only after Leena's found and sets about in the direction of school to look for Alex. Kara uses her force on Alex who doesn't believe that she's his former girlfriend and finally Kara breaks down and begs him to tell her where her sister is as she believes him to be the killer. Alex denies the accusation and Kara finds that Alex had felt so guilty after being unable to stop her from dying that he had promised to look after her sister. Kara asks him to call Derek and Wanda while she remembers that she had loved Alex once but had stolen him from her sister. When Derek and Wanda arrive and she questions them, Alex immediately catches up on their lie and is hit on the head. Kara is forcefully led to the auditorium where she finds her sister drugged and tied to a chair. Derek and Wanda reveal that they were the killers and had killed Kara because she had refused to help them cheat during exams. They tell her that they had blackmailed Kara into doing it before but she had then developed a conscience and refused to help them any further. Disappointed with their average status, Derek and Wanda killed her before she could go to the principal and had them expelled, but not before Kara had written a message in a textbook. Derek and Wanda hadn't realized what Kara had done until after they killed two more girls. Kara feels a surge of anger and guilt and starts to fight them knowing that she could take them on. But she soon sees Death who has come to claim a soul, Kara remembers her earlier phone conversation with Armine who had told her that Death would need a soul to take back with him. Kara sacrifices herself and extracts a promise from her sister to let her go this time. Later, Kara finds herself awakened once again and finds herself outside the school where Derek and Wanda are being taken to prison while her family has come together again. She wishes that she could be with them but realizes that she now belongs in the light.