The film is based in Madurai, where Siva (Mohanlal), a local don, rules the city with an iron hand and is openly involved in innumerable illegal activities, unmindful of the law. Shakti's (Vijay) biological father, who worked as Siva's driver is killed at the hands of a cop while trying to save his boss and his pregnant wife. Shakti is adopted by Siva and grows up to be his trusted and powerful right hand man, in charge of all his shady operations. The newly-appointed Commissioner of Police (Pradeep Rawat) insults Siva by arresting him. Deeply offended, Siva decides to make Shakti a police officer. He believes that having his own man inside the police department could be very useful for his operations. Since witnessing his father's death, Shakti has only contempt for all police officers. But despite his reluctance, Siva forces Shakti to become a cop. How this plan backfires on him forms the rest of the story.