Sakthi lives with her 6-year-old daughter Adhithi after her divorce from her husband. Adhithi is terrified when she hears a voice calling her name in her flat. After celebrating her birthday, Adhithi discovers a baby doll near her floor lift and hears that voice again, this time asking her to accept the doll as her birthday gift. Adhithi begins to develop feelings for that voice and begins to see a ghostly figure to which she becomes attached. Adhithi sketches the ghostly image in a piece of paper one night and writes her name as Anne. When Sakthi notices this drawing, she becomes concerned and consults a psychiatrist, who recommends her to spend more time with her child. Sakthi becomes mentally upset when one of her friends informs her that Adhithi does not resemble Sakthi or Siva, her husband. She and Adhithi do a DNA test, and the findings are negative - their DNA does not match. Upset with this, she directly goes to her husband Siva's apartment and demands to take her biological daughter Avanthika with her who was living with her father all these years. Following a heated debate between the two, Siva shares the following flashback: Avanthika was admitted to the intensive care unit shortly after birth because she had a respiratory condition. Siva, with the assistance of a doctor, takes another newborn infant from another ward and sets it beside Sakthi, who is still sleeping. He does this to protect Sakthi since she is mentally too weak to hear that her own baby has a respiratory condition. When his own baby heals, Siva tells Sakthi the truth and returns another baby to the doctor. However, this other baby appears to be the kid of Anne , who dies of a post-delivery fit after discovering that her baby was not present when she awoke from labour pains. Siva, noticing this, decides to take the baby with him and replaces it when Sakthi is sleeping. After hearing this story, Sakthi welcomes both children as her own, and the pair marries and moves into Sakthi's flat together. But things worsen as Adhithi becomes possessive of Sakthi as she observes Sakthi becoming more close to Avanthika. Avantika is now terrified of the ghostly presence and feels insecure around her mother. Siva sees Anne as that ghostly form one day and quickly realises Anne was haunting Avantika in order for her to have her own child Adhithi to be cared after by Sakthi. When he told Sakthi this, she didn't trust him and instead assumed Siva was intending to separate her from her own daughter. After a heated dispute with Sakthi, he returns to his previous flat to avoid the issue worsening and to protect his own daughter from Anne. Sakthi is shocked later in her flat when she discovers Adhithi playing with Anne and takes Adhithi with her as she drives away from her flat. She calls Siva and describes what she saw in her flat. Siva advises that Sakthi return Adhithi to an orphanage in order to put an end to Anne's actions. However, Sakthi rejects this notion and drives away from Siva, taking Adhithi with her. She also tells Siva on the phone while driving her car that she has grown more attached to Adhithi than Avanthika and that she would rather stay with Adhithi forever. Anne, who was hearing all of this, burst into tears because of what she had done to this family. But, as fate would have it, Sakthi's car is involved in an accident that kills Adhithi and severely injures Sakthi. The film's final credits show Sakthi standing in front of an elevator with the doll in her hand. Siva comforts her and returns her to her flat. Adhithi peeks out and sees them going away from the location.
