The movie opens with Vidyadharan serving time in a prison.
During the flashback it is revealed that Vidyadharan, a small village clocksmith and a widower, lived with his only daughter. His wife died from a snake bite years ago. However, his childhood friend and love interest Sarojini lives next to his house. Sarojini's husband left her spending just a single night with her leaving her with a teenage daughter. Vidyadharan is phobic of snakes possibly due to his wife's death. He carries a flashlight through the village lanes even in broad daylight.
Although Vidyadharan's extended family disapproves of his on-off relationship with Sarojini, his daughter and Sarojini's daughter are like sisters. We are introduced to a host of supporting characters in the sleepy palakkadan hamlet like Vidyadaran's sister, his friend near watch repairing shop, the drunkard who carries a rifle, etc.
Their simple world in the sleepy hamlet is turned upside down one day when Sarojini's teenage daughter goes missing. After much investigation, her body is found inside a cave on a hilltop. It is revealed that she was gang raped. There is no evidence pointing to anyone: yet another case of sexual offence against girls in the area.
Vidyadharan feels that it is a drunk hunter who is behind the crime. The police in the meanwhile investigate and declare the hunter to be innocent. Vidyadharan confronts the hunter and a battle of words ensue between them. During the confrontation, Vidyadharan accidentally kills the hunter and is sent to prison.
He leads a calm life inside the prison campus and is a pet of the jail warden. While Sarojini visits Vidyadharan frequently, his daughter had been taken away by her mother's family.
During one of her visits, Sarojini tells him that she met Vidyadharan's daughter and that she has grown up. He wishes to meet her but is informed that her mother's family will not give her the permission to do so. During the visit, Sarojini also apprises Vidyadharan about the increasing number of rapes and molestations and recounts the fate of her daughter. Vidyadharan is visibly disturbed by this social scenario, more so as his daughter is growing up in such a society. He starts developing the anxiousness and insecurity of a father of an adolescent girl.
Vidyadharan's release date comes nearer. During one of Sarojini's visit, he tells her that, upon release, he would go to a land far away with Sarojini and his daughter and will live happily. He entrusts Sarojini the job of bringing his daughter from her maternal home after convincing her. Sarojini agrees.
As days are nearing for the release, Vidyadharan is happy and roams around the jail. During his regular afternoon strolls, to his surprise, Vidyadharan find a hole in the thick jail wall. Vidyadharan tactfully clears the hole and uses his magnifying lens to check if he is able to view something. To his luck, he finds that the eyesize hole is dug through the entire thickness and he is able to see the hilltop just outside the jail. Vidyadharan is amused but is careful not to let the inmates and constables know about it, especially with his release date being so close.
During his free time, Vidyadharan sees the small family of blind singers living on the hilltop and their beautiful daughter. He sees their small-time existence and how beautifully they sing. He finds that one of the jail constables is intervening in their life, telling them to move out of the place. When Vidyadharan meets this constable inside the jail, he is unable to express his anger. He recollects the misbehaviour of the same man once Sarojini visited him. Vidyadharan concludes that the constable is not a good man.
The other day Vidyadharan witnesses a celebration in the small hut of blind singers. It is revealed that the beautiful daughter has become adolescent. Vidyadharan is very happy as his own daughter would be of the same age.
As he looks on another day, while the beautiful teenage girl is alone in the hut, he sees the cruel poilceman going inside. This is followed by the girl's shrieks and violent cry for help. As she comes running outside, Vidyadharan sees the police constable chasing her like a mad dog. Vidyadharan tries to seek help, but his voice is not heard. Stranded within the campus, Vidyadharan is totally helpless.
The blind singers come back home to find the shocking news. They are shattered and, in the heat of loss they suffered, they decide to punish themselves by setting fire to the house and themselves. Vidyadharan watches as the silent spectator.
The next morning the constable comes in front of the inmates for checking. Vidyadharan has lost all control by now and he attacks the constable accusing him of the life of the three innocent people. The inmates and the jail warden run in. Vidyadharan shows the hole and describes the entire episode to the jailer. The jailer hears in disbelief and orders both Vidyadharan and the constable to be taken for medical aid.
The jailer inspects the hole and feels sorry for Vidyadharan. As he leaves, the camera zooms in towards the hole and reveals nothing but brick. The hole and the entire episode was an imagination of Vidyadharan's turbulent state of mind.
As Sarojini comes to the jail with Vidyadharan's daughter, he has a blank face, turns towards them and asks "Aara?" [Who are you?]. The movie concludes with the aerial shot of a train departing from the station.
