Stephen (Vijayaraghavan) is the circle inspector in charge of the anti-goonda squad but he himself is the head of a gang whose members are Acid (Saji Soman) and Sathan (Prithviraj Sukumaran). Sathan is a murderer and a rapist who is willing to do any crime for money. He meets a girl Angelina (Chandra Lakshman) whom he rapes and later she becomes pregnant. Angelina who was to be a nun is thus expelled from church and later Sathan starts having a soft corner for her. He decides to turn a new leaf in life but Stephen does not agree to his idea. And when Stephen is suspended from the department his anger towards Sathan increases. This leads to a bloody climax on a railway track. The Night of the climax, Saathan meets Angelina at the church, where she is staying. There he reveals he was the one who had raped her. After the revelation he leaves the church. Stephen and the police chase and arrest Sathan. Stephen plans to kill Saathan, after bloody fight, by laying him over the tracks. But Sathan grabs Stephen's leg and the train crushes them both to death. Next day Angelina is shocked at the news of Sathan's death, whom she had started to love.
All through the story's narrative, we hear the voice of the (late) director A. K. Lohithadas as the narrator, by the end of the film we know that Lohithadas was actually researching for a new movie script, when we finally see Angelina as a single mother to a son fathered by Saathan. The movie closes with a street side poster of Lohithadas's new movie, which is based on Saathan's life. The sequel of the movie, Asuravithu, starring Asif Ali as Saathan's son was released on January 6, 2012.
The movie performed well at the box office,largely drawing youth audience to the theatre. the movie is considered as "Prithviraj"'s notable performance in his early movies.