Arjun Bhagwat (Emraan Hashmi) is a money-hungry ex-police officer involved in crime. An atheist (nastik), he regularly visits church to donate money to orphans. Priya (Jacqueline Fernandez), a model, is in a passionate but confused relationship with Arjun. Priya is in love with Arjun, who lusts after her. At the beginning of the film, he forces upon her but the relationship continues.
Arjun makes a deal with a gangster and pimp, Sameer, in order to solve the mystery of unexplained disappearance of his prostitutes. While investigating, Arjun finds a phone number linked to the missing girls. He tells Sameer to send a prostitute to the number. Sameer decides to send Reshma (Sulagna Panigrahi), a 17-year-old college newcomer in the business, who has entered prostitution to feed her family, though keeps this a secret from them. Reshma is sent to the house of Dheeraj Pandey (Prashant Narayanan), who is actually a psychopathic murderer responsible for torturing and killing the missing hookers. He decides to do the same with Reshma and throws her in a dark well, with the intention of torturing her till she dies.
Arjun finds out that Dheeraj is the murderer and tells the police. While Dheeraj is held in jail, the commissioner calls a psychiatrist to extract his confession. Dheeraj tells the doctor that he kills women because he thinks they take advantage of men. He also reveals that he castrated himself and became a eunuch to get rid of his sex addiction, with the help of a fellow eunuch and big-shot politician, Nirmala Pandit. Dheeraj is eventually let out under Nirmala Pandit’s influence. Meanwhile, Reshma escapes from the well and tries to find her way out through the forest.
Arjun meets Dheeraj’s family, who reveal that Dheeraj used to beat his wife. He next meets a private dancer, Sonia, who had also been tortured by Dheeraj, but managed to escape. Arjun then meets an idol-maker who used to work with Dheeraj. The maker tells him that Dheeraj used to make idols of devils instead of deities and killed the factory-owner who tried to stop him. Inspector Sadaa (Sudhanshu Pandey) informs Arjun that Dheeraj is free, and the police try to track him down as quickly as possible. Nirmala and Dheeraj enter the same temple where Reshma is hiding. Nirmala and the priest, who had both been unaware of Dheeraj’s true nature, are killed by Dheeraj, but not before the priest reveals that Reshma is there. Dheeraj finds the terrified Reshma and brutally murders her, escaping just before Arjun and the cops arrive. Arjun finds Reshma’s body and breaks down, feeling guilty and responsible for her death.