Terrifying and thrilling, this tale of terror opens with Dinesh (Vijay Antony) and his boss (Y. G. Mahendra) visiting a psychiatrist. Dinesh tells the doctor that he had been listening to a voice for a few days and it has been troubling him. Upon questioning the source of the voice, Dinesh tells that the voice sounds like that of God, if he were present really. The doctor asks Dinesh to come along with him for a personal treatment where Dinesh tells him that he had killed his friend Ravi.
The doctor asks Dinesh to relax and hypnotises him in his sleep where he asks him various questions. It is revealed that a clever Dinesh had been recently married to a beautiful orphan Aishwarya (Arundhati Nair) who had contacted him through a matrimonial site. After their return from their Honeymoon trip, Dinesh starts hallucinating and hearing voices in his head. Also, his best friend Ravi who comes to help him gets killed in an accident due to Dinesh. The voice in Dinesh's head keeps telling him to die and Dinesh sees miserable things on TV screens, computer screens and distorted bruised faces near the windows. After the treatment, the doctor tells Dinesh not to wander off alone and tells his boss that Dinesh is disturbed, and is being haunted by memories of his past life.
On returning home, a disturbed Dinesh aimlessly runs away from home and reaches Tanjavore in a train. While in the train he hears the same voice in his head directing him to that village and he names Sharma, Gopal, Natraj and Jayalakshmi. As soon as he gets down he hires an auto to find what happened to him and who is the voice. Upon investigating he finds out a picture of Sharma (Vijay Antony in his previous life) was a respected bachelor who adopted a boy Gopal and later married Jayalakshmi (Arundhati Nair).
Things go smooth until Nataraj (Arav) becomes employed in the same school. Jayalakshmi and Nataraj have an illicit affair, and she becomes pregnant, but the child is passed off as belonging to Sharma. Despite rumours surrounding the pregnancy, Sharma loves and cares for the baby. However, when he tries to finally confront Natraj, the baby accidentally dies. Jayalakshmi runs away after this incident. Two weeks later, both Sharma and Gopal are found dead on the banks of a river and Jayalakshmi, Nataraj disappear into thin air. The case gets closed as they are not tracked down.
Unbeknownst to all, Jayalakshmi returns and meets Sharma asking for forgiveness, which he readily does. Jayalakshmi feeds him food which is poisoned and later Nataraj and Jayalakshmi kill him and Gopal as a revenge for killing their baby. Then, they abandon their bodies near a river bank and run away.
Back in present day, a deranged Dinesh wakes up to find himself in the mental asylum where he is being treated. Aishwarya comes to him with a tiffin box to feed him. Dinesh who has Sharma's soul inside him charges upon Aishwarya who looks like Jayalakshmi because he and Gopal were killed the same way. He is sedated and left inside his room for a few days where Sharma refuses to accept leave Dinesh's body. In the meanwhile Aishwarya goes missing leaving behind a letter after she gets a call from Thomas.
It is revealed that Aishwarya had married Dinesh, just to test a drug on him. But guilt drives her to become a committed wife, and she refuses to do any harm to him. Apparently, it was the effect of the drug that caused him to remember his past. Thomas calls up Dinesh and asks him to return and hand over the evidence that was stolen from his guest house.
When Dinesh comes with it, the gang Aishwarya had worked for reveals to Dinesh that she is a sex worker, who prostituted herself to the whole gang before she became his wife. Dinesh accepts the fact and asks to take Aishwarya away with him. A scuffle ensues and Dinesh is drugged with high doses of the chemical. This causes him to get extra ordinary power while his body is taken over by Sharma and he defeats everyone before heading towards Aishwarya with murderous intent.
Aishwarya who is pregnant with Dinesh's child tells him that she is sorry for what she was forced to do to him, and that she wishes to be his wife and the mother of his child. She also saves him from getting killed by Dr. Christopher (Kamal Krishna), who runs the drug scam and also illegal organ mafia business. In the process of saving Dinesh, she gets injured badly. Sharma who is in Dinesh's body acts in defense and kills Dr. Christopher.
Later, in the media, the wrongdoing of the gang and their drugs it is exposed. Also, they reveal that Dinesh was a victim as he was used as a test subject and Aishwarya who was wounded is alright now.